diff --git a/slack-lint-checks/src/main/java/slack/lint/retrofit/RetrofitUsageDetector.kt b/slack-lint-checks/src/main/java/slack/lint/retrofit/RetrofitUsageDetector.kt
index b2c772a4..3f4aa493 100644
--- a/slack-lint-checks/src/main/java/slack/lint/retrofit/RetrofitUsageDetector.kt
+++ b/slack-lint-checks/src/main/java/slack/lint/retrofit/RetrofitUsageDetector.kt
@@ -61,12 +61,19 @@ class RetrofitUsageDetector : Detector(), SourceCodeScanner {
           return
         }
 
+        val isMultipart = FQCN_MULTIPART in annotationsByFqcn
+        if (isMultipart && !isBodyMethod) {
+          node.report("@Multipart requires @PUT, @POST, or @PATCH.")
+          return
+        }
+
         val hasPath =
           (httpAnnotation.findDeclaredAttributeValue("value")?.evaluate() as? String)?.isNotBlank()
             ?: false
 
         var hasBodyParam = false
         var hasFieldParams = false
+        var hasPartParams = false
         var hasUrlParam = false
 
         for (parameter in node.uastParameters) {
@@ -101,6 +108,12 @@ class RetrofitUsageDetector : Detector(), SourceCodeScanner {
             } else {
               hasUrlParam = true
             }
+          } else if (parameter.hasAnnotation(FQCN_PART)) {
+            if (!isBodyMethod) {
+              httpAnnotation.report("@Part param requires @PUT, @POST, or @PATCH.")
+            } else {
+              hasPartParams = true
+            }
           }
         }
 
@@ -112,7 +125,13 @@ class RetrofitUsageDetector : Detector(), SourceCodeScanner {
               quickFixData = LintFix.create().removeNode(context, annotation.sourcePsiElement!!),
             )
           }
-        } else if (isBodyMethod && !hasBodyParam && !hasFieldParams) {
+        } else if (isMultipart) {
+          if (hasBodyParam || hasFieldParams) {
+            httpAnnotation.report("@Multipart methods should only contain @Part parameters.")
+          } else if (!hasPartParams) {
+            httpAnnotation.report("@Multipart methods should contain at least one @Part parameter.")
+          }
+        } else if (isBodyMethod && !hasBodyParam && !hasFieldParams && !hasPartParams) {
           httpAnnotation.report("This annotation requires an `@Body` parameter.")
         }
         if (!hasPath && !hasUrlParam) {
@@ -144,7 +163,9 @@ class RetrofitUsageDetector : Detector(), SourceCodeScanner {
     private val HTTP_BODY_ANNOTATIONS =
       setOf("retrofit2.http.PATCH", "retrofit2.http.POST", "retrofit2.http.PUT")
     private const val FQCN_FORM_ENCODED = "retrofit2.http.FormUrlEncoded"
+    private const val FQCN_MULTIPART = "retrofit2.http.Multipart"
     private const val FQCN_FIELD = "retrofit2.http.Field"
+    private const val FQCN_PART = "retrofit2.http.Part"
     private const val FQCN_FIELD_MAP = "retrofit2.http.FieldMap"
     private const val FQCN_BODY = "retrofit2.http.Body"
     private const val FQCN_URL = "retrofit2.http.Url"
diff --git a/slack-lint-checks/src/test/java/slack/lint/retrofit/RetrofitUsageDetectorTest.kt b/slack-lint-checks/src/test/java/slack/lint/retrofit/RetrofitUsageDetectorTest.kt
index a8d4c00a..325e8ef9 100644
--- a/slack-lint-checks/src/test/java/slack/lint/retrofit/RetrofitUsageDetectorTest.kt
+++ b/slack-lint-checks/src/test/java/slack/lint/retrofit/RetrofitUsageDetectorTest.kt
@@ -90,6 +90,8 @@ class RetrofitUsageDetectorTest : BaseSlackLintTest() {
 
             import retrofit2.http.Body
             import retrofit2.http.GET
+            import retrofit2.http.Multipart
+            import retrofit2.http.Part
             import retrofit2.http.POST
 
             interface Example {
@@ -104,6 +106,22 @@ class RetrofitUsageDetectorTest : BaseSlackLintTest() {
 
               @POST("/")
               fun correct(@Body input: String): String
+
+              @Multipart
+              @POST("/")
+              fun multipartCorrect(@Part input: String): String
+
+              @Multipart
+              @GET("/")
+              fun multipartBadMethod(@Part input: String): String
+
+              @Multipart
+              @POST("/")
+              fun multipartBadParameterType(@Body input: String): String
+
+              @Multipart
+              @POST("/")
+              fun multipartMissingPartParameter(): String
             }
           """
           )
@@ -112,17 +130,26 @@ class RetrofitUsageDetectorTest : BaseSlackLintTest() {
       .run()
       .expect(
         """
-        src/test/Example.kt:8: Error: @Body param requires @PUT, @POST, or @PATCH. [RetrofitUsage]
-          @GET("/")
-          ~~~~~~~~~
-        src/test/Example.kt:11: Error: This annotation requires an @Body parameter. [RetrofitUsage]
-          @POST("/")
-          ~~~~~~~~~~
-        src/test/Example.kt:15: Error: Duplicate @Body param!. [RetrofitUsage]
-          fun doubleBody(@Body input: String, @Body input2: String): String
-                                              ~~~~~~~~~~~~~~~~~~~~
-        3 errors, 0 warnings
-        """
+          src/test/Example.kt:10: Error: @Body param requires @PUT, @POST, or @PATCH. [RetrofitUsage]
+            @GET("/")
+            ~~~~~~~~~
+          src/test/Example.kt:13: Error: This annotation requires an @Body parameter. [RetrofitUsage]
+            @POST("/")
+            ~~~~~~~~~~
+          src/test/Example.kt:17: Error: Duplicate @Body param!. [RetrofitUsage]
+            fun doubleBody(@Body input: String, @Body input2: String): String
+                                                ~~~~~~~~~~~~~~~~~~~~
+          src/test/Example.kt:28: Error: @Multipart requires @PUT, @POST, or @PATCH. [RetrofitUsage]
+            fun multipartBadMethod(@Part input: String): String
+                ~~~~~~~~~~~~~~~~~~
+          src/test/Example.kt:31: Error: @Multipart methods should only contain @Part parameters. [RetrofitUsage]
+            @POST("/")
+            ~~~~~~~~~~
+          src/test/Example.kt:35: Error: @Multipart methods should contain at least one @Part parameter. [RetrofitUsage]
+            @POST("/")
+            ~~~~~~~~~~
+          6 errors, 0 warnings
+          """
           .trimIndent()
       )
   }