diff --git a/src/poetry/packages/locker.py b/src/poetry/packages/locker.py
index 7fa0e6ffce9..57765ffa440 100644
--- a/src/poetry/packages/locker.py
+++ b/src/poetry/packages/locker.py
@@ -378,6 +378,10 @@ def _dump_package(self, package: Package) -> dict[str, Any]:
                     constraint["tag"] = dependency.tag
                 elif dependency.rev:
                     constraint["rev"] = dependency.rev
+
+                if dependency.directory:
+                    constraint["subdirectory"] = dependency.directory
+
             else:
                 constraint["version"] = str(dependency.pretty_constraint)
 
diff --git a/tests/packages/test_locker.py b/tests/packages/test_locker.py
index 23022d41c66..1595b40e6ce 100644
--- a/tests/packages/test_locker.py
+++ b/tests/packages/test_locker.py
@@ -865,6 +865,15 @@ def test_locker_dumps_dependency_information_correctly(
             "F", {"git": "https://github.com/python-poetry/poetry.git", "branch": "foo"}
         )
     )
+    package_a.add_dependency(
+        Factory.create_dependency(
+            "G",
+            {
+                "git": "https://github.com/python-poetry/poetry.git",
+                "subdirectory": "bar",
+            },
+        )
+    )
 
     packages = [package_a]
 
@@ -891,6 +900,7 @@ def test_locker_dumps_dependency_information_correctly(
 D = {{path = "distributions/demo-0.1.0.tar.gz"}}
 E = {{url = "https://python-poetry.org/poetry-1.2.0.tar.gz"}}
 F = {{git = "https://github.com/python-poetry/poetry.git", branch = "foo"}}
+G = {{git = "https://github.com/python-poetry/poetry.git", subdirectory = "bar"}}
 
 [metadata]
 lock-version = "2.0"