diff --git a/gradle.properties b/gradle.properties
index 90c16abce8a..4e8762868bd 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -15,7 +15,7 @@
 #
 
 # A version of the Kotlin "toolchain" (compiler, runtime, stdlib etc) used by the build script.
-buildKotlinVersion=1.2.20
+buildKotlinVersion=1.2.40
 remoteRoot=konan_tests
 #kotlinCompilerModule=org.jetbrains.kotlin:kotlin-compiler:1.1-SNAPSHOT
 # Download artifacts of https://teamcity.jetbrains.com/viewType.html?buildTypeId=Kotlin_120_Compiler