diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3e0d8b51f3..daee5ae803 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,10 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
 ### Added
 
+
+- Added a friendly error message when attempting to call `Trainer.save_checkpoint()` without a model attached ([#12772](https://github.com/PyTorchLightning/pytorch-lightning/pull/12772))
+
+
 - Enabled `torch.inference_mode` for evaluation and prediction ([#12715](https://github.com/PyTorchLightning/pytorch-lightning/pull/12715))
 
 
diff --git a/pytorch_lightning/trainer/trainer.py b/pytorch_lightning/trainer/trainer.py
index 05e3112e60..41e47684fd 100644
--- a/pytorch_lightning/trainer/trainer.py
+++ b/pytorch_lightning/trainer/trainer.py
@@ -2364,6 +2364,11 @@ class Trainer(
             storage_options: parameter for how to save to storage, passed to ``CheckpointIO`` plugin
 
         """
+        if self.model is None:
+            raise AttributeError(
+                "Saving a checkpoint is only possible if a model is attached to the Trainer. Did you call"
+                " `Trainer.save_checkpoint()` before calling `Trainer.{fit,validate,test,predict}`?"
+            )
         self._checkpoint_connector.save_checkpoint(filepath, weights_only=weights_only, storage_options=storage_options)
 
     """
diff --git a/tests/trainer/test_trainer.py b/tests/trainer/test_trainer.py
index e13e41eda3..316384a20c 100644
--- a/tests/trainer/test_trainer.py
+++ b/tests/trainer/test_trainer.py
@@ -2133,3 +2133,10 @@ def test_trainer_config_device_ids(monkeypatch, trainer_kwargs, expected_device_
     trainer = Trainer(**trainer_kwargs)
     assert trainer.device_ids == expected_device_ids
     assert trainer.num_devices == len(expected_device_ids)
+
+
+def test_trainer_save_checkpoint_no_model_attached():
+    trainer = Trainer()
+    assert trainer.model is None
+    with pytest.raises(AttributeError, match="Saving a checkpoint is only possible if a model is attached"):
+        trainer.save_checkpoint("checkpoint.ckpt")