diff --git a/newsfragments/1163.bugfix b/newsfragments/1163.bugfix
new file mode 100644
index 00000000..9f8567fa
--- /dev/null
+++ b/newsfragments/1163.bugfix
@@ -0,0 +1 @@
+- Fixed error when merging args in list and dict syntax
diff --git a/podman_compose.py b/podman_compose.py
index 60c77cad..018e513c 100755
--- a/podman_compose.py
+++ b/podman_compose.py
@@ -1607,6 +1607,9 @@ def normalize_service(service, sub_dir=""):
             for k, v in build["additional_contexts"].items():
                 new_additional_contexts.append(f"{k}={v}")
             build["additional_contexts"] = new_additional_contexts
+    if "build" in service and "args" in service["build"]:
+        if isinstance(build["args"], dict):
+            build["args"] = norm_as_list(build["args"])
     for key in ("command", "entrypoint"):
         if key in service:
             if isinstance(service[key], str):
diff --git a/tests/unit/test_can_merge_build.py b/tests/unit/test_can_merge_build.py
index 8fce6e18..20e0863d 100644
--- a/tests/unit/test_can_merge_build.py
+++ b/tests/unit/test_can_merge_build.py
@@ -68,6 +68,16 @@ class TestCanMergeBuild(unittest.TestCase):
             {"build": {"dockerfile": "./dockerfile-1", "args": ["ENV2=2"]}},
             {"build": {"dockerfile": "./dockerfile-1", "args": ["ENV1=1", "ENV2=2"]}},
         ),
+        (
+            {"build": {"dockerfile": "./dockerfile-1", "args": {"ENV1": "1"}}},
+            {"build": {"dockerfile": "./dockerfile-2", "args": {"ENV2": "2"}}},
+            {"build": {"dockerfile": "./dockerfile-2", "args": ["ENV1=1", "ENV2=2"]}},
+        ),
+        (
+            {"build": {"dockerfile": "./dockerfile-1", "args": ["ENV1=1"]}},
+            {"build": {"dockerfile": "./dockerfile-2", "args": {"ENV2": "2"}}},
+            {"build": {"dockerfile": "./dockerfile-2", "args": ["ENV1=1", "ENV2=2"]}},
+        ),
     ])
     def test_parse_compose_file_when_multiple_composes(self, input, override, expected):
         compose_test_1 = {"services": {"test-service": input}}