diff --git a/args.c b/args.c
index f6c604a..8059789 100644
--- a/args.c
+++ b/args.c
@@ -383,6 +383,11 @@ static int spank_option_container_save(int val, const char *optarg, int remote)
 		return (-1);
 	}
 
+	if (optarg[strlen(optarg) - 1] == '/') {
+		slurm_error("pyxis: --container-save: target is a directory");
+		return (-1);
+	}
+
 	/* Slurm can call us twice with the same value, check if it's a different value than before. */
 	if (pyxis_args.container_save != NULL) {
 		if (strcmp(pyxis_args.container_save, optarg) == 0)
diff --git a/tests/invalid_args.bats b/tests/invalid_args.bats
index ec5c3cc..1031ee7 100644
--- a/tests/invalid_args.bats
+++ b/tests/invalid_args.bats
@@ -72,3 +72,14 @@ load ./common
     run_srun_unchecked --container-env FOO, --container-image=ubuntu:22.04 true
     [ "${status}" -ne 0 ]
 }
+
+@test "invalid arg: --container-save=<directory>" {
+    run_srun_unchecked --container-save=/tmp/ --container-image=ubuntu:24.04 true
+    [ "${status}" -ne 0 ]
+
+    run_srun_unchecked --container-save=/ --container-image=ubuntu:24.04 true
+    [ "${status}" -ne 0 ]
+
+    run_srun_unchecked --container-save=./ --container-image=ubuntu:24.04 true
+    [ "${status}" -ne 0 ]
+}