diff --git a/mantidimaging/core/data/dataset.py b/mantidimaging/core/data/dataset.py
index 60c49d160cb..b0121a83567 100644
--- a/mantidimaging/core/data/dataset.py
+++ b/mantidimaging/core/data/dataset.py
@@ -201,10 +201,6 @@ def is_processed(self) -> bool:
         return False
 
 
-class MixedDataset(Dataset):
-    pass
-
-
 class StrictDataset(Dataset):
     pass
 
diff --git a/mantidimaging/core/data/test/mixeddataset_test.py b/mantidimaging/core/data/test/mixeddataset_test.py
deleted file mode 100644
index 8ec61d0b11c..00000000000
--- a/mantidimaging/core/data/test/mixeddataset_test.py
+++ /dev/null
@@ -1,61 +0,0 @@
-# Copyright (C) 2024 ISIS Rutherford Appleton Laboratory UKRI
-# SPDX - License - Identifier: GPL-3.0-or-later
-from __future__ import annotations
-
-import unittest
-
-from mantidimaging.core.data.dataset import MixedDataset, _get_stack_data_type
-from mantidimaging.test_helpers.unit_test_helper import generate_images
-
-
-class MixedDatasetTest(unittest.TestCase):
-
-    def setUp(self) -> None:
-        self.image_stacks = [generate_images() for _ in range(3)]
-        self.mixed_dataset = MixedDataset(stacks=self.image_stacks)
-
-    def test_all(self):
-        self.assertListEqual(self.mixed_dataset.all, self.image_stacks)
-
-    def test_delete_stack_from_stacks_list(self):
-        prev_stacks = self.image_stacks.copy()
-        self.mixed_dataset.delete_stack(self.image_stacks[-1].id)
-        self.assertListEqual(self.mixed_dataset.all, prev_stacks[:-1])
-
-    def test_delete_stack_from_recons_list(self):
-        [self.mixed_dataset.add_recon(generate_images()) for _ in range(2)]
-        recons = self.mixed_dataset.recons.copy()
-
-        id_to_remove = recons[-1].id
-        self.mixed_dataset.delete_stack(id_to_remove)
-        self.assertNotIn(recons[-1], self.mixed_dataset.all)
-
-    def test_delete_stack_failure(self):
-        with self.assertRaises(KeyError):
-            self.mixed_dataset.delete_stack("nonexistent-id")
-
-    def test_all_ids(self):
-        self.assertListEqual(self.mixed_dataset.all_image_ids, [image_stack.id for image_stack in self.image_stacks])
-
-    def test_sinograms_in_all(self):
-        self.assertListEqual(self.mixed_dataset._stacks, self.mixed_dataset.all)
-        self.mixed_dataset.sinograms = sinograms = generate_images()
-        self.assertListEqual(self.mixed_dataset._stacks + [sinograms], self.mixed_dataset.all)
-
-    def test_delete_sinograms(self):
-        self.mixed_dataset.sinograms = sinograms = generate_images()
-        self.mixed_dataset.delete_stack(sinograms.id)
-        self.assertNotIn(sinograms, self.mixed_dataset.all)
-
-    def test_get_stack_data_type_returns_recon(self):
-        recon = generate_images()
-        recon_id = recon.id
-        dataset = MixedDataset()
-        dataset.recons.append(recon)
-        self.assertEqual(_get_stack_data_type(recon_id, dataset), "Recon")
-
-    def test_get_stack_data_type_returns_images(self):
-        images = generate_images()
-        images_id = images.id
-        dataset = MixedDataset(stacks=[images])
-        self.assertEqual(_get_stack_data_type(images_id, dataset), "Images")