diff --git a/swh/loader/package/opam/loader.py b/swh/loader/package/opam/loader.py
--- a/swh/loader/package/opam/loader.py
+++ b/swh/loader/package/opam/loader.py
@@ -10,9 +10,20 @@
 
 import attr
 
-from swh.loader.package.loader import BasePackageInfo, PackageLoader
+from swh.loader.package.loader import (
+    BasePackageInfo,
+    PackageLoader,
+    RawExtrinsicMetadataCore,
+)
 from swh.loader.package.utils import cached_method
-from swh.model.model import Person, Revision, RevisionType, Sha1Git
+from swh.model.model import (
+    MetadataAuthority,
+    MetadataAuthorityType,
+    Person,
+    Revision,
+    RevisionType,
+    Sha1Git,
+)
 from swh.storage.interface import StorageInterface
 
 
@@ -103,6 +114,9 @@
     def get_package_file(self, version: str) -> str:
         return f"{self.get_package_dir()}/{self.get_package_name(version)}/opam"
 
+    def get_metadata_authority(self):
+        return MetadataAuthority(type=MetadataAuthorityType.FORGE, url=self.opam_url)
+
     @cached_method
     def _compute_versions(self) -> List[str]:
         """Compute the versions using opam internals
@@ -171,9 +185,10 @@
         """Return the most recent version of the package as default."""
         return self._compute_versions()[-1]
 
-    def get_enclosed_single_line_field(self, field, version) -> Optional[str]:
+    def _opam_show_version_file(self, version: str, extra_params: List[str] = []):
         package_file = self.get_package_file(version)
-        result = opam_read(
+
+        return opam_read(
             [
                 "opam",
                 "show",
@@ -185,11 +200,13 @@
                 self.opam_root,
                 "--file",
                 package_file,
-                "--field",
-                field,
+                *extra_params,
             ]
         )
 
+    def get_enclosed_single_line_field(self, field, version) -> Optional[str]:
+        result = self._opam_show_version_file(version, ["--field", field])
+
         # Sanitize the result if any (remove trailing \n and enclosing ")
         return result.strip().strip('"') if result else None
 
@@ -211,7 +228,17 @@
         committer = Person(fullname=fullname, name=None, email=None)
 
         yield self.get_package_name(version), OpamPackageInfo(
-            url=url, filename=None, author=author, committer=committer, version=version
+            url=url,
+            filename=None,
+            author=author,
+            committer=committer,
+            version=version,
+            directory_extrinsic_metadata=[
+                RawExtrinsicMetadataCore(
+                    metadata=self._opam_show_version_file(version).encode(),
+                    format="opam-package-definition",
+                )
+            ],
         )
 
     def build_revision(
diff --git a/swh/loader/package/opam/tests/test_opam.py b/swh/loader/package/opam/tests/test_opam.py
--- a/swh/loader/package/opam/tests/test_opam.py
+++ b/swh/loader/package/opam/tests/test_opam.py
@@ -4,10 +4,23 @@
 # See top-level LICENSE file for more information
 
 
+from swh.loader.package import __version__
+from swh.loader.package.loader import RawExtrinsicMetadataCore
 from swh.loader.package.opam.loader import OpamLoader, OpamPackageInfo
 from swh.loader.tests import assert_last_visit_matches, check_snapshot, get_stats
 from swh.model.hashutil import hash_to_bytes
-from swh.model.model import Person, Snapshot, SnapshotBranch, TargetType
+from swh.model.model import (
+    MetadataAuthority,
+    MetadataAuthorityType,
+    MetadataFetcher,
+    Person,
+    RawExtrinsicMetadata,
+    Snapshot,
+    SnapshotBranch,
+    TargetType,
+)
+from swh.model.swhids import CoreSWHID, ExtendedObjectType, ExtendedSWHID, ObjectType
+from swh.storage.interface import PagedResult
 
 
 def test_opam_loader_no_opam_repository_fails(swh_storage, tmpdir, datadir):
@@ -181,7 +194,6 @@
     expected_package_info = OpamPackageInfo(
         url="https://github.com/OCamlPro/ocb/archive/0.1.tar.gz",
         filename=None,
-        directory_extrinsic_metadata=[],
         author=Person(
             fullname=b"OCamlPro <contact@ocamlpro.com>", name=None, email=None
         ),
@@ -189,6 +201,11 @@
             fullname=b"OCamlPro <contact@ocamlpro.com>", name=None, email=None
         ),
         version="0.1",
+        directory_extrinsic_metadata=[
+            RawExtrinsicMetadataCore(
+                metadata=b'opam-version: "2.0"\n', format="opam-package-definition",
+            )
+        ],
     )
 
     assert branch_name == expected_branch_name
@@ -202,3 +219,58 @@
 
     assert revision.author == expected_package_info.author
     assert revision.committer == expected_package_info.committer
+
+
+def test_opam_metadata(tmpdir, requests_mock_datadir, swh_storage, datadir):
+    opam_url = f"file://{datadir}/fake_opam_repo"
+    opam_root = tmpdir
+    opam_instance = "loadertest"
+
+    opam_package = "ocb"
+    url = f"opam+{opam_url}/packages/{opam_package}"
+
+    loader = OpamLoader(
+        swh_storage,
+        url,
+        opam_root,
+        opam_instance,
+        opam_url,
+        opam_package,
+        initialize_opam_root=True,
+    )
+
+    actual_load_status = loader.load()
+
+    assert actual_load_status["status"] == "eventful"
+
+    expected_revision_id = b"o\xad\x7f=\x07\xbb\xaah\xdbI(\xb0'\x10z\xfc\xff\x06x\x1b"
+
+    revision = swh_storage.revision_get([expected_revision_id])[0]
+    assert revision is not None
+
+    revision_swhid = CoreSWHID(
+        object_type=ObjectType.REVISION, object_id=expected_revision_id
+    )
+    directory_swhid = ExtendedSWHID(
+        object_type=ExtendedObjectType.DIRECTORY, object_id=revision.directory
+    )
+    metadata_authority = MetadataAuthority(
+        type=MetadataAuthorityType.FORGE, url=opam_url,
+    )
+    expected_metadata = [
+        RawExtrinsicMetadata(
+            target=directory_swhid,
+            authority=metadata_authority,
+            fetcher=MetadataFetcher(
+                name="swh.loader.package.opam.loader.OpamLoader", version=__version__,
+            ),
+            discovery_date=loader.visit_date,
+            format="opam-package-definition",
+            metadata=b'opam-version: "2.0"\n',
+            origin=url,
+            revision=revision_swhid,
+        )
+    ]
+    assert swh_storage.raw_extrinsic_metadata_get(
+        directory_swhid, metadata_authority,
+    ) == PagedResult(next_page_token=None, results=expected_metadata,)