diff --git a/doc/changes/12236.md b/doc/changes/12236.md
new file mode 100644
index 00000000000..480c45a1245
--- /dev/null
+++ b/doc/changes/12236.md
@@ -0,0 +1 @@
+- Add support for %{ocaml-config:ox} (#12236, @jonludlam)
diff --git a/src/ocaml-config/ocaml_config.ml b/src/ocaml-config/ocaml_config.ml
index 430fac3c1a8..0be8f6aaf22 100644
--- a/src/ocaml-config/ocaml_config.ml
+++ b/src/ocaml-config/ocaml_config.ml
@@ -136,6 +136,7 @@ type t =
   ; natdynlink_supported : bool
   ; supports_shared_libraries : bool
   ; windows_unicode : bool
+  ; ox : bool
   }
 
 let version t = t.version
@@ -190,6 +191,7 @@ let cmt_magic_number t = t.cmt_magic_number
 let natdynlink_supported t = t.natdynlink_supported
 let supports_shared_libraries t = t.supports_shared_libraries
 let windows_unicode t = t.windows_unicode
+let ox t = t.ox
 
 let to_list
       { version = _
@@ -244,6 +246,7 @@ let to_list
       ; natdynlink_supported
       ; supports_shared_libraries
       ; windows_unicode
+      ; ox
       }
   : (string * Value.t) list
   =
@@ -298,6 +301,7 @@ let to_list
   ; "natdynlink_supported", Bool natdynlink_supported
   ; "supports_shared_libraries", Bool supports_shared_libraries
   ; "windows_unicode", Bool windows_unicode
+  ; "ox", Bool ox
   ]
 ;;
 
@@ -357,6 +361,7 @@ let by_name
       ; natdynlink_supported
       ; supports_shared_libraries
       ; windows_unicode
+      ; ox
       }
       name
   : Value.t option
@@ -413,6 +418,7 @@ let by_name
   | "natdynlink_supported" -> Some (Bool natdynlink_supported)
   | "supports_shared_libraries" -> Some (Bool supports_shared_libraries)
   | "windows_unicode" -> Some (Bool windows_unicode)
+  | "ox" -> Some (Bool ox)
   | _ -> None
 ;;
 
@@ -640,13 +646,14 @@ let make vars =
       let stdlib = Path.external_ (Path.External.of_string standard_library) in
       Path.relative stdlib "Makefile.config"
     in
-    let vars = Vars.load_makefile_config file in
+    let ox = get_bool vars "ox" in
+    let makefile_vars = Vars.load_makefile_config file in
     let module Getters =
       Vars.Getters (struct
         let origin = Origin.Makefile_config file
       end)
     in
-    let supports_shared_libraries = get_bool vars "SUPPORTS_SHARED_LIBRARIES" in
+    let supports_shared_libraries = get_bool makefile_vars "SUPPORTS_SHARED_LIBRARIES" in
     { version
     ; version_string
     ; standard_library_default
@@ -699,6 +706,7 @@ let make vars =
     ; natdynlink_supported
     ; supports_shared_libraries
     ; windows_unicode
+    ; ox
     }
   with
   | t -> Ok t
diff --git a/src/ocaml-config/ocaml_config.mli b/src/ocaml-config/ocaml_config.mli
index 67aa330d786..eee15c0bd6f 100644
--- a/src/ocaml-config/ocaml_config.mli
+++ b/src/ocaml-config/ocaml_config.mli
@@ -118,6 +118,7 @@ val cmt_magic_number : t -> string
 val natdynlink_supported : t -> bool
 val supports_shared_libraries : t -> bool
 val windows_unicode : t -> bool
+val ox : t -> bool
 
 (** {1 Values} *)
 
diff --git a/test/blackbox-tests/test-cases/ocaml-config-ox.t b/test/blackbox-tests/test-cases/ocaml-config-ox.t
new file mode 100644
index 00000000000..d129b82b173
--- /dev/null
+++ b/test/blackbox-tests/test-cases/ocaml-config-ox.t
@@ -0,0 +1,14 @@
+Check that %{ocaml-config:ox} doesn't fail. This test does not explicitly
+check the value of the parameter.
+
+  $ cat > "dune-project" <<EOF
+  > (lang dune 1.0)
+  > EOF
+
+  $ cat > "dune" <<EOF
+  > (rule
+  >   (targets x)
+  >     (action (with-stdout-to %{targets} (echo %{ocaml-config:ox}))))
+  > EOF
+
+  $ dune build x
diff --git a/test/blackbox-tests/test-cases/oxcaml/ocaml-config-ox-true.t b/test/blackbox-tests/test-cases/oxcaml/ocaml-config-ox-true.t
new file mode 100644
index 00000000000..1ea172d0ff9
--- /dev/null
+++ b/test/blackbox-tests/test-cases/oxcaml/ocaml-config-ox-true.t
@@ -0,0 +1,15 @@
+Check that %{ocaml-config:ox} works and returns true
+
+  $ cat > "dune-project" <<EOF
+  > (lang dune 1.0)
+  > EOF
+
+  $ cat > "dune" <<EOF
+  > (rule
+  >   (targets x)
+  >     (action (with-stdout-to %{targets} (echo %{ocaml-config:ox}))))
+  > EOF
+
+  $ dune build x
+  $ cat _build/default/x
+  true