diff --git a/bin/test.sh b/bin/test.sh
index adfc3e9ea909cdc6cb46908df7b87b85e0ec564c..be51144b495c37c213c58683b086590dea3b713a 100755
--- a/bin/test.sh
+++ b/bin/test.sh
@@ -81,6 +81,7 @@ function Usage
     echo "  -s|--save           save dune logs into $DUNE_LOG"
     echo "  -v|--verbose        print executed commands"
     echo "  -j|--jobs <jobs>    run no more than <jobs> commands simultaneously."
+    echo "  --watch             run dune in watch mode."
     echo "  --coverage          compute test coverage in html format"
     echo "  --coverage-xml      compute test coverage in Cobertura XML format"
     echo "  --coverage-json     compute test coverage in Coveralls JSON format"
@@ -171,6 +172,9 @@ do
             DUNE_OPT+="--auto-promote "
             UPDATE=yes
             ;;
+        "--watch")
+            DUNE_OPT+="--watch "
+            ;;
         "-v"|"--verbose")
             DUNE_OPT+="--display=short "
             VERBOSE=yes