diff --git a/datasets/LJSpeech.py b/datasets/LJSpeech.py
index d8eb66b4..e72a66e0 100644
--- a/datasets/LJSpeech.py
+++ b/datasets/LJSpeech.py
@@ -3,6 +3,7 @@ import numpy as np
 import collections
 import librosa
 import torch
+import random
 from torch.utils.data import Dataset
 
 from utils.text import text_to_sequence
@@ -17,8 +18,10 @@ class MyDataset(Dataset):
                  outputs_per_step,
                  text_cleaner,
                  ap,
+                 batch_group_size=0,
                  min_seq_len=0):
         self.root_dir = root_dir
+        self.batch_group_size = batch_group_size
         self.wav_dir = os.path.join(root_dir, 'wavs')
         self.csv_dir = os.path.join(root_dir, csv_file)
         with open(self.csv_dir, "r", encoding="utf8") as f:
@@ -30,7 +33,7 @@ class MyDataset(Dataset):
         self.ap = ap
         print(" > Reading LJSpeech from - {}".format(root_dir))
         print(" | > Number of instances : {}".format(len(self.frames)))
-        self._sort_frames()
+        self.sort_frames()
 
     def load_wav(self, filename):
         try:
@@ -39,8 +42,8 @@ class MyDataset(Dataset):
         except RuntimeError as e:
             print(" !! Cannot read file : {}".format(filename))
 
-    def _sort_frames(self):
-        r"""Sort sequences in ascending order"""
+    def sort_frames(self):
+        r"""Sort text sequences in ascending order"""
         lengths = np.array([len(ins[1]) for ins in self.frames])
 
         print(" | > Max length sequence {}".format(np.max(lengths)))
@@ -58,6 +61,15 @@ class MyDataset(Dataset):
                 new_frames.append(self.frames[idx])
         print(" | > {} instances are ignored by min_seq_len ({})".format(
             len(ignored), self.min_seq_len))
+        # shuffle batch groups
+        if self.batch_group_size > 0:
+            print(" | > Batch group shuffling is active.")
+            for i in range(len(new_frames) // self.batch_group_size):
+                offset = i * self.batch_group_size
+                end_offset = offset + self.batch_group_size
+                temp_frames = new_frames[offset : end_offset]
+                random.shuffle(temp_frames)
+                new_frames[offset : end_offset] = temp_frames
         self.frames = new_frames
 
     def __len__(self):
diff --git a/tests/loader_tests.py b/tests/loader_tests.py
index a53cf635..b80f3e74 100644
--- a/tests/loader_tests.py
+++ b/tests/loader_tests.py
@@ -66,6 +66,49 @@ class TestLJSpeechDataset(unittest.TestCase):
                 assert mel_input.shape[0] == c.batch_size
                 assert mel_input.shape[2] == c.num_mels
 
+    def test_batch_group_shuffle(self):
+        if ok_ljspeech:
+            dataset = LJSpeech.MyDataset(
+                os.path.join(c.data_path_LJSpeech),
+                os.path.join(c.data_path_LJSpeech, 'metadata.csv'),
+                c.r,
+                c.text_cleaner,
+                ap=self.ap,
+                batch_group_size=16,
+                min_seq_len=c.min_seq_len)
+
+            dataloader = DataLoader(
+                dataset,
+                batch_size=2,
+                shuffle=True,
+                collate_fn=dataset.collate_fn,
+                drop_last=True,
+                num_workers=c.num_loader_workers)
+
+            frames = dataset.frames
+            for i, data in enumerate(dataloader):
+                if i == self.max_loader_iter:
+                    break
+                text_input = data[0]
+                text_lengths = data[1]
+                linear_input = data[2]
+                mel_input = data[3]
+                mel_lengths = data[4]
+                stop_target = data[5]
+                item_idx = data[6]
+
+                neg_values = text_input[text_input < 0]
+                check_count = len(neg_values)
+                assert check_count == 0, \
+                    " !! Negative values in text_input: {}".format(check_count)
+                # TODO: more assertion here
+                assert linear_input.shape[0] == c.batch_size
+                assert mel_input.shape[0] == c.batch_size
+                assert mel_input.shape[2] == c.num_mels
+            dataloader.dataset.sort_frames()
+            assert frames[0] != dataloader.dataset.frames[0]
+
+
     def test_padding(self):
         if ok_ljspeech:
             dataset = LJSpeech.MyDataset(
diff --git a/train.py b/train.py
index e1df221d..d8a75b1d 100644
--- a/train.py
+++ b/train.py
@@ -191,7 +191,6 @@ def train(model, criterion, criterion_st, data_loader, optimizer, optimizer_st,
     tb.add_scalar('TrainEpochLoss/StopLoss', avg_stop_loss, current_step)
     tb.add_scalar('Time/EpochTime', epoch_time, epoch)
     epoch_time = 0
-
     return avg_linear_loss, current_step
 
 
@@ -361,6 +360,7 @@ def main(args):
         c.r,
         c.text_cleaner,
         ap=ap,
+        batch_group_size=16*c.batch_size,
         min_seq_len=c.min_seq_len)
 
     train_loader = DataLoader(
@@ -374,7 +374,7 @@ def main(args):
 
     if c.run_eval:
         val_dataset = Dataset(
-            c.data_path, c.meta_file_val, c.r, c.text_cleaner, ap=ap)
+            c.data_path, c.meta_file_val, c.r, c.text_cleaner, ap=ap, batch_group_size=0)
 
         val_loader = DataLoader(
             val_dataset,
@@ -444,6 +444,8 @@ def main(args):
             flush=True)
         best_loss = save_best_model(model, optimizer, train_loss, best_loss,
                                     OUT_PATH, current_step, epoch)
+         # shuffle batch groups
+        train_loader.dataset.sort_frames()
 
 
 if __name__ == '__main__':