diff --git a/runtime/internal/lib/time/sleep.go b/runtime/internal/lib/time/sleep.go
index 3f5914c2..08c180fa 100644
--- a/runtime/internal/lib/time/sleep.go
+++ b/runtime/internal/lib/time/sleep.go
@@ -15,7 +15,7 @@ import (
 // Sleep pauses the current goroutine for at least the duration d.
 // A negative or zero duration causes Sleep to return immediately.
 func Sleep(d Duration) {
-	c.Usleep(c.Uint(d.Nanoseconds()))
+	c.Usleep(c.Uint(d.Microseconds()))
 }
 
 // Interface to timers implemented in package runtime.