diff --git a/.idea/inspectionProfiles/Project_Default.xml b/.idea/inspectionProfiles/Project_Default.xml
index bdb1b11bb..163aa4ffe 100644
--- a/.idea/inspectionProfiles/Project_Default.xml
+++ b/.idea/inspectionProfiles/Project_Default.xml
@@ -1,6 +1,7 @@
 <component name="InspectionProjectProfileManager">
   <profile version="1.0">
     <option name="myName" value="Project Default" />
+    <inspection_tool class="IllegalIdentifier" enabled="false" level="ERROR" enabled_by_default="false" />
     <inspection_tool class="PreviewAnnotationInFunctionWithParameters" enabled="true" level="ERROR" enabled_by_default="true">
       <option name="composableFile" value="true" />
       <option name="previewFile" value="true" />
diff --git a/yorkie/src/main/kotlin/dev/yorkie/document/crdt/TextInfo.kt b/yorkie/src/main/kotlin/dev/yorkie/document/crdt/TextInfo.kt
index 825af6288..6d8bf8ca3 100644
--- a/yorkie/src/main/kotlin/dev/yorkie/document/crdt/TextInfo.kt
+++ b/yorkie/src/main/kotlin/dev/yorkie/document/crdt/TextInfo.kt
@@ -54,7 +54,7 @@ internal data class TextValue(
 
     fun toJson(): String {
         val attrs = _attributes.nodeKeyValueMap.entries.joinToString(",") {
-            """"${it.key}":"${escapeString(it.value)}""""
+            """"${escapeString(it.key)}":"${escapeString(it.value)}""""
         }
         return if (attrs.isEmpty()) {
             """{"val":"${escapeString(content)}"}"""
diff --git a/yorkie/src/main/kotlin/dev/yorkie/document/json/EscapeString.kt b/yorkie/src/main/kotlin/dev/yorkie/document/json/EscapeString.kt
index e317d699a..340827d6d 100644
--- a/yorkie/src/main/kotlin/dev/yorkie/document/json/EscapeString.kt
+++ b/yorkie/src/main/kotlin/dev/yorkie/document/json/EscapeString.kt
@@ -6,7 +6,6 @@ package dev.yorkie.document.json
 internal fun escapeString(str: String): String {
     return str.replace("\\", "\\\\")
         .replace("\"", "\\\"")
-        .replace("\'", "\\'")
         .replace("\n", "\\n")
         .replace("\r", "\\r")
         .replace("\b", "\\b")
diff --git a/yorkie/src/main/kotlin/dev/yorkie/document/json/JsonStringifier.kt b/yorkie/src/main/kotlin/dev/yorkie/document/json/JsonStringifier.kt
index 821a1f4d9..4d6a3d965 100644
--- a/yorkie/src/main/kotlin/dev/yorkie/document/json/JsonStringifier.kt
+++ b/yorkie/src/main/kotlin/dev/yorkie/document/json/JsonStringifier.kt
@@ -49,7 +49,7 @@ internal object JsonStringifier {
             is CrdtObject -> {
                 buffer.append("{")
                 forEach { (key, value) ->
-                    buffer.append(""""$key":""")
+                    buffer.append(""""${escapeString(key)}":""")
                     value.toJsonStringInternal(buffer)
                     if (key != last().first) {
                         buffer.append(",")
diff --git a/yorkie/src/test/kotlin/dev/yorkie/document/DocumentTest.kt b/yorkie/src/test/kotlin/dev/yorkie/document/DocumentTest.kt
index a851ebe40..0f7fe47cc 100644
--- a/yorkie/src/test/kotlin/dev/yorkie/document/DocumentTest.kt
+++ b/yorkie/src/test/kotlin/dev/yorkie/document/DocumentTest.kt
@@ -1,5 +1,6 @@
 package dev.yorkie.document
 
+import com.google.gson.JsonParser
 import dev.yorkie.assertJsonContentEquals
 import dev.yorkie.document.json.JsonArray
 import dev.yorkie.document.json.JsonText
@@ -265,4 +266,41 @@ class DocumentTest {
             assertEquals(0, target.garbageLength)
         }
     }
+
+    @Test
+    fun `should handle escape string for strings containing single quotes`() {
+        runTest {
+            target.updateAsync { root, _ ->
+                root["str"] = "I'm Yorkie"
+            }.await()
+            assertEquals("""{"str":"I'm Yorkie"}""", target.toJson())
+            assertEquals(
+                "I'm Yorkie",
+                JsonParser.parseString(target.toJson()).asJsonObject.get("str").asString,
+            )
+
+            target.updateAsync { root, _ ->
+                root["str"] = """I\\'m Yorkie"""
+            }.await()
+            assertEquals("""{"str":"I\\\\'m Yorkie"}""", target.toJson())
+            assertEquals(
+                """I\\'m Yorkie""",
+                JsonParser.parseString(target.toJson()).asJsonObject.get("str").asString,
+            )
+        }
+    }
+
+    @Test
+    fun `should handle escape string for object keys`() {
+        runTest {
+            target.updateAsync { root, _ ->
+                root["""it"s"""] = "Yorkie"
+            }.await()
+            assertEquals("""{"it\"s":"Yorkie"}""", target.toJson())
+            assertEquals(
+                "Yorkie",
+                JsonParser.parseString(target.toJson()).asJsonObject.get("""it"s""").asString,
+            )
+        }
+    }
 }
diff --git a/yorkie/src/test/kotlin/dev/yorkie/document/crdt/TextValueTest.kt b/yorkie/src/test/kotlin/dev/yorkie/document/crdt/TextValueTest.kt
new file mode 100644
index 000000000..8c81452b1
--- /dev/null
+++ b/yorkie/src/test/kotlin/dev/yorkie/document/crdt/TextValueTest.kt
@@ -0,0 +1,29 @@
+package dev.yorkie.document.crdt
+
+import com.google.gson.JsonParser
+import dev.yorkie.document.time.TimeTicket
+import kotlin.test.assertEquals
+import org.junit.Test
+
+class TextValueTest {
+
+    @Test
+    fun `should handle escape string for attributes`() {
+        val text = TextValue(
+            """va"lue""",
+            Rht().apply {
+                set("""it"s""", """York\ie""", TimeTicket.InitialTimeTicket)
+                set("its", "Yorkie", TimeTicket.InitialTimeTicket)
+            },
+        )
+        assertEquals(
+            """{"attrs":{"it\"s":"York\\ie","its":"Yorkie"},"val":"va\"lue"}""",
+            text.toJson(),
+        )
+        val json = JsonParser.parseString(text.toJson()).asJsonObject
+        assertEquals("""va"lue""", json.get("val").asString)
+        val attrs = json.getAsJsonObject("attrs")
+        assertEquals("""York\ie""", attrs.get("""it"s""").asString)
+        assertEquals("Yorkie", attrs.get("its").asString)
+    }
+}
diff --git a/yorkie/src/test/kotlin/dev/yorkie/json/StringEscapingTest.kt b/yorkie/src/test/kotlin/dev/yorkie/json/StringEscapingTest.kt
index c0866f453..5104726b6 100644
--- a/yorkie/src/test/kotlin/dev/yorkie/json/StringEscapingTest.kt
+++ b/yorkie/src/test/kotlin/dev/yorkie/json/StringEscapingTest.kt
@@ -9,7 +9,7 @@ class StringEscapingTest {
     @Test
     fun `should escape a string with case1`() {
         val target = "1\\2\"3'4\n5\r6\t7\b8\u000C9\u20280\u2029"
-        val escaped = "1\\\\2\\\"3\\'4\\n5\\r6\\t7\\b8\\f9\\u20280\\u2029"
+        val escaped = "1\\\\2\\\"3'4\\n5\\r6\\t7\\b8\\f9\\u20280\\u2029"
         assertEquals(escaped, escapeString(target))
     }