diff --git a/src/test/kotlin/com/mapk/core/EnumMapperTest.kt b/src/test/kotlin/com/mapk/core/EnumMapperTest.kt
new file mode 100644
index 0000000..ed3fb76
--- /dev/null
+++ b/src/test/kotlin/com/mapk/core/EnumMapperTest.kt
@@ -0,0 +1,36 @@
+package com.mapk.core
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertNull
+import org.junit.jupiter.api.DisplayName
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.assertThrows
+import org.junit.jupiter.params.ParameterizedTest
+import org.junit.jupiter.params.provider.EnumSource
+
+@DisplayName("EnumMapperのテスト")
+class EnumMapperTest {
+    enum class JvmLanguage {
+        Java, Scala, Groovy, Kotlin
+    }
+
+    @ParameterizedTest
+    @EnumSource(value = JvmLanguage::class)
+    @DisplayName("正常系")
+    fun test(value: JvmLanguage) {
+        assertEquals(value, EnumMapper.getEnum(JvmLanguage::class.java, value.name))
+    }
+
+    @Test
+    @DisplayName("null/空文字列入力")
+    fun isNull() {
+        assertNull(EnumMapper.getEnum(JvmLanguage::class.java, null))
+        assertNull(EnumMapper.getEnum(JvmLanguage::class.java, ""))
+    }
+
+    @Test
+    @DisplayName("存在しないもの")
+    fun isNotExisting() {
+        assertThrows<IllegalArgumentException> { EnumMapper.getEnum(JvmLanguage::class.java, "C") }
+    }
+}
diff --git a/src/test/kotlin/com/mapk/core/FunctionsTest.kt b/src/test/kotlin/com/mapk/core/FunctionsTest.kt
new file mode 100644
index 0000000..5164183
--- /dev/null
+++ b/src/test/kotlin/com/mapk/core/FunctionsTest.kt
@@ -0,0 +1,88 @@
+package com.mapk.core
+
+import com.mapk.annotations.KConstructor
+import kotlin.reflect.full.companionObjectInstance
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertNull
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.DisplayName
+import org.junit.jupiter.api.Nested
+import org.junit.jupiter.api.Test
+
+@DisplayName("共通利用関数関連のテスト")
+class FunctionsTest {
+    class NoCompanionObject
+
+    @Target(AnnotationTarget.FUNCTION)
+    @Retention(AnnotationRetention.RUNTIME)
+    @MustBeDocumented
+    annotation class TestAnnotation1
+
+    @Target(AnnotationTarget.FUNCTION)
+    @Retention(AnnotationRetention.RUNTIME)
+    @MustBeDocumented
+    annotation class TestAnnotation2
+
+    class WithCompanionObject {
+        companion object {
+            @KConstructor
+            fun kConstructor() {}
+
+            @TestAnnotation2
+            fun testAnnotation1() {}
+
+            @TestAnnotation2
+            fun testAnnotation2() {}
+        }
+    }
+
+    @Nested
+    @DisplayName("コンパニオンオブジェクトから指定したアノテーションを取得するテスト")
+    inner class GetAnnotatedFunctionsFromCompanionObject {
+        @Test
+        @DisplayName("コンパニオンオブジェクトが無い場合")
+        fun noCompanionObject() {
+            assertNull(NoCompanionObject::class.getAnnotatedFunctionsFromCompanionObject<KConstructor>())
+        }
+
+        @Test
+        @DisplayName("コンパニオンオブジェクトが有るが関数が取れない場合")
+        fun withCompanionObjectButNotFound() {
+            assertNull(WithCompanionObject::class.getAnnotatedFunctionsFromCompanionObject<TestAnnotation1>())
+        }
+
+        @Test
+        @DisplayName("単体取得")
+        fun kConstructor() {
+            val result =
+                WithCompanionObject::class.getAnnotatedFunctionsFromCompanionObject<KConstructor>()!!
+
+            assertEquals(WithCompanionObject::class.companionObjectInstance!!, result.first)
+            assertEquals(1, result.second.size)
+            assertEquals("kConstructor", result.second.single().name)
+        }
+
+        @Test
+        @DisplayName("複数取得")
+        fun testAnnotation() {
+            val result =
+                WithCompanionObject::class.getAnnotatedFunctionsFromCompanionObject<TestAnnotation2>()!!
+
+            assertEquals(WithCompanionObject::class.companionObjectInstance!!, result.first)
+            assertEquals(2, result.second.size)
+            val names = listOf("testAnnotation1", "testAnnotation2")
+            assertTrue(names.contains(result.second[0].name))
+            assertTrue(names.contains(result.second[1].name))
+        }
+    }
+
+    data class InnerClass(val arg: Int)
+    data class DataClass(val innerClass: InnerClass)
+
+    @Test
+    @DisplayName("パラメータからの型取得テスト")
+    fun getKClassTest() {
+        val param = ::DataClass.parameters.single()
+        assertEquals(InnerClass::class, param.getKClass())
+    }
+}