diff --git a/protocol/src/main/scala/sbt/internal/bsp/BuildServerConnection.scala b/protocol/src/main/scala/sbt/internal/bsp/BuildServerConnection.scala
index 9c4e55c83..9b21dd31e 100644
--- a/protocol/src/main/scala/sbt/internal/bsp/BuildServerConnection.scala
+++ b/protocol/src/main/scala/sbt/internal/bsp/BuildServerConnection.scala
@@ -28,6 +28,7 @@ object BuildServerConnection {
     val sbtLaunchJar = classPath
       .split(File.pathSeparator)
       .find(jar => SbtLaunchJar.findFirstIn(jar).nonEmpty)
+      .map(_.replaceAllLiterally(" ", "%20"))
     val argv =
       Vector(
         s"$javaHome/bin/java",