diff --git a/src/tools/compiletest/src/main.rs b/src/tools/compiletest/src/main.rs
index 3f2cd3ae232ba..503b624114a2a 100644
--- a/src/tools/compiletest/src/main.rs
+++ b/src/tools/compiletest/src/main.rs
@@ -487,11 +487,6 @@ fn configure_lldb(config: &Config) -> Option<Config> {
         return None;
     }
 
-    // Some older versions of LLDB seem to have problems with multiple
-    // instances running in parallel, so only run one test thread at a
-    // time.
-    env::set_var("RUST_TEST_THREADS", "1");
-
     Some(Config { debugger: Some(Debugger::Lldb), ..config.clone() })
 }