diff --git a/backend/src/main/java/reviewme/highlight/service/HighlightService.java b/backend/src/main/java/reviewme/highlight/service/HighlightService.java
index 13e1891d2..ddcfdc45a 100644
--- a/backend/src/main/java/reviewme/highlight/service/HighlightService.java
+++ b/backend/src/main/java/reviewme/highlight/service/HighlightService.java
@@ -1,19 +1,13 @@
 package reviewme.highlight.service;
 
-import java.util.HashMap;
 import java.util.List;
-import java.util.Map;
-import java.util.stream.Collectors;
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 import reviewme.highlight.domain.Highlight;
-import reviewme.highlight.domain.HighlightLines;
 import reviewme.highlight.repository.HighlightRepository;
-import reviewme.highlight.service.dto.HighlightIndexRangeRequest;
-import reviewme.highlight.service.dto.HighlightRequest;
-import reviewme.highlight.service.dto.HighlightedLineRequest;
 import reviewme.highlight.service.dto.HighlightsRequest;
+import reviewme.highlight.service.mapper.HighlightMapper;
 import reviewme.highlight.service.validator.HighlightValidator;
 import reviewme.review.domain.TextAnswer;
 import reviewme.review.domain.TextAnswers;
@@ -30,6 +24,7 @@ public class HighlightService {
     private final TextAnswerRepository textAnswerRepository;
 
     private final HighlightValidator highlightValidator;
+    private final HighlightMapper highlightMapper;
 
     @Transactional
     public void editHighlight(HighlightsRequest highlightsRequest, String reviewRequestCode) {
@@ -37,60 +32,14 @@ public void editHighlight(HighlightsRequest highlightsRequest, String reviewRequ
                 .orElseThrow(() -> new ReviewGroupNotFoundByReviewRequestCodeException(reviewRequestCode))
                 .getId();
         List<TextAnswer> textAnswersByIds = textAnswerRepository.findAllById(highlightsRequest.getUniqueAnswerIds());
-        TextAnswers textAnswers = new TextAnswers(textAnswersByIds);
 
         highlightValidator.validate(highlightsRequest, reviewGroupId);
-        Map<Long, HighlightLines> highlightLines = mapHighlightLines(highlightsRequest, textAnswers);
-
-        deleteBeforeHighlight(highlightsRequest.questionId(), textAnswers);
-        saveHighlights(highlightLines);
-    }
-
-    private Map<Long, HighlightLines> mapHighlightLines(HighlightsRequest highlightsRequest, TextAnswers textAnswers) {
-        Map<Long, List<Integer>> answerLineIndexes = highlightsRequest.highlights()
-                .stream()
-                .collect(Collectors.toMap(HighlightRequest::answerId, HighlightRequest::getLineIndexes));
-
-        Map<Long, HighlightLines> highlightLinesByAnswerId = new HashMap<>();
-        for (HighlightRequest highlightRequest : highlightsRequest.highlights()) {
-            long answerId = highlightRequest.answerId();
-            highlightLinesByAnswerId.put(answerId,
-                    mapHighlightLine(highlightRequest, textAnswers.get(answerId), answerLineIndexes.get(answerId))
-            );
-        }
-        return highlightLinesByAnswerId;
-    }
+        List<Highlight> highlights = highlightMapper.mapToHighlights(highlightsRequest, textAnswersByIds);
 
-    private HighlightLines mapHighlightLine(HighlightRequest highlightRequest,
-                                       TextAnswer answer, List<Integer> answerLineIndex) {
-        HighlightLines highlightLines = new HighlightLines(answer.getContent(), answerLineIndex);
-        for (HighlightedLineRequest lineRequest : highlightRequest.lines()) {
-            for (HighlightIndexRangeRequest rangeRequest : lineRequest.ranges()) {
-                highlightLines.addRange(lineRequest.index(), rangeRequest.startIndex(), rangeRequest.endIndex());
-            }
-        }
-        return highlightLines;
-    }
-
-    private void deleteBeforeHighlight(long questionId, TextAnswers textAnswers) {
-        List<Long> answerIds = textAnswers.getIdsByQuestionId(questionId);
+        TextAnswers textAnswers = new TextAnswers(textAnswersByIds);
+        List<Long> answerIds = textAnswers.getIdsByQuestionId(highlightsRequest.questionId());
         highlightRepository.deleteAllByIds(answerIds);
-    }
 
-    private void saveHighlights(Map<Long, HighlightLines> highlightLines) {
-        List<Highlight> highlights = highlightLines.entrySet()
-                .stream()
-                .flatMap(highlightLinesByAnswer ->
-                        createHighlight(highlightLinesByAnswer.getKey(), highlightLinesByAnswer.getValue()).stream())
-                .collect(Collectors.toList());
         highlightRepository.saveAll(highlights);
     }
-
-    private List<Highlight> createHighlight(long answerId, HighlightLines lines) {
-        return lines.getLines()
-                .stream()
-                .flatMap(line -> line.getRanges().stream()
-                        .map(range -> new Highlight(answerId, line.getLineIndex(), range)))
-                .toList();
-    }
 }
diff --git a/backend/src/test/java/reviewme/highlight/service/HighlightServiceTest.java b/backend/src/test/java/reviewme/highlight/service/HighlightServiceTest.java
index 41af0734b..138b36629 100644
--- a/backend/src/test/java/reviewme/highlight/service/HighlightServiceTest.java
+++ b/backend/src/test/java/reviewme/highlight/service/HighlightServiceTest.java
@@ -95,34 +95,26 @@ class HighlightServiceTest {
         long reviewGroupId = reviewGroupRepository.save(ReviewGroupFixture.리뷰_그룹(reviewRequestCode, "groupAccessCode"))
                 .getId();
 
-        TextAnswer textAnswer1 = new TextAnswer(questionId, "text answer1");
-        TextAnswer textAnswer2 = new TextAnswer(questionId, "text answer2");
-        Review review = reviewRepository.save(new Review(templateId, reviewGroupId, List.of(textAnswer1, textAnswer2)));
-
+        TextAnswer textAnswer = new TextAnswer(questionId, "text answer1");
+        Review review = reviewRepository.save(new Review(templateId, reviewGroupId, List.of(textAnswer)));
         highlightRepository.save(new Highlight(1, 1, new HighlightRange(1, 1)));
 
         int startIndex = 2;
         int endIndex = 2;
-        int lineIndex = 0;
         HighlightIndexRangeRequest indexRangeRequest = new HighlightIndexRangeRequest(startIndex, endIndex);
-        HighlightedLineRequest lineRequest1 = new HighlightedLineRequest(lineIndex, List.of(indexRangeRequest));
-        HighlightedLineRequest lineRequest2 = new HighlightedLineRequest(lineIndex, List.of(indexRangeRequest));
-        HighlightRequest highlightRequest1 = new HighlightRequest(textAnswer1.getId(), List.of(lineRequest1));
-        HighlightRequest highlightRequest2 = new HighlightRequest(textAnswer2.getId(), List.of(lineRequest2));
-        HighlightsRequest highlightsRequest = new HighlightsRequest(questionId,
-                List.of(highlightRequest1, highlightRequest2));
+        HighlightedLineRequest lineRequest = new HighlightedLineRequest(0, List.of(indexRangeRequest));
+        HighlightRequest highlightRequest = new HighlightRequest(textAnswer.getId(), List.of(lineRequest));
+        HighlightsRequest highlightsRequest = new HighlightsRequest(questionId, List.of(highlightRequest));
 
         // when
         highlightService.editHighlight(highlightsRequest, reviewRequestCode);
 
         // then
         List<Highlight> highlights = highlightRepository.findAll();
-        HighlightRange position = new HighlightRange(startIndex, endIndex);
         assertAll(
-                () -> assertThat(highlights.get(0).getAnswerId()).isEqualTo(textAnswer1.getId()),
-                () -> assertThat(highlights.get(1).getAnswerId()).isEqualTo(textAnswer2.getId()),
-                () -> assertThat(highlights.get(0).getHighlightRange()).isEqualTo(position),
-                () -> assertThat(highlights.get(0).getHighlightRange()).isEqualTo(position)
+                () -> assertThat(highlights.get(0).getAnswerId()).isEqualTo(textAnswer.getId()),
+                () -> assertThat(highlights.get(0).getHighlightRange()).isEqualTo(
+                        new HighlightRange(startIndex, endIndex))
         );
     }
 }