diff --git a/egs/aishell/ASR/conformer_ctc/generate_CTC_label.py b/egs/aishell/ASR/conformer_ctc/generate_CTC_label.py
new file mode 100755
index 000000000..26a333e67
--- /dev/null
+++ b/egs/aishell/ASR/conformer_ctc/generate_CTC_label.py
@@ -0,0 +1,207 @@
+#!/usr/bin/env python3
+# Author: Haoyu Tang
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import argparse
+import logging
+import os
+from pathlib import Path
+
+from lhotse.features.io import LilcomChunkyWriter
+from lhotse.features.base import store_feature_array
+import torch
+import torch.nn as nn
+from asr_datamodule import AishellAsrDataModule
+from conformer import Conformer
+
+from icefall.checkpoint import average_checkpoints, load_checkpoint
+from icefall.lexicon import Lexicon
+from icefall.utils import (
+    AttributeDict,
+    setup_logger,
+    write_error_stats,
+)
+
+
+def get_parser():
+    parser = argparse.ArgumentParser(
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter
+    )
+
+    parser.add_argument(
+        "--epoch",
+        type=int,
+        default=49,
+        help="It specifies the checkpoint to use for decoding."
+        "Note: Epoch counts from 0.",
+    )
+    parser.add_argument(
+        "--avg",
+        type=int,
+        default=20,
+        help="Number of checkpoints to average. Automatically select "
+        "consecutive checkpoints before the checkpoint specified by "
+        "'--epoch'. ",
+    )
+
+    parser.add_argument(
+        "--exp-dir",
+        type=str,
+        default="conformer_ctc/exp",
+        help="The experiment dir",
+    )
+    parser.add_argument(
+        "--lang-dir",
+        type=str,
+        default="data/lang_char",
+        help="The lang dir",
+    )
+
+    return parser
+
+
+def get_params() -> AttributeDict:
+    params = AttributeDict(
+        {
+            # parameters for conformer
+            "subsampling_factor": 4,
+            "feature_dim": 80,
+            "nhead": 4,
+            "attention_dim": 512,
+            "num_encoder_layers": 12,
+            "num_decoder_layers": 6,
+            "vgg_frontend": False,
+            "use_feat_batchnorm": True,
+        }
+    )
+    return params
+
+
+def generate_ctc_label_batch(
+    params: AttributeDict,
+    model: nn.Module,
+    batch: dict,
+    device: torch.device,
+):
+    feature = batch["inputs"]
+    assert feature.ndim == 3
+    feature = feature.to(device)
+    # at entry, feature is (N, T, C)
+
+    supervisions = batch["supervisions"]
+    nnet_output, memory, memory_key_padding_mask = model(feature, supervisions)
+    return nnet_output
+
+
+def generate_ctc_label_dataset(
+    dl: torch.utils.data.DataLoader,
+    params: AttributeDict,
+    model: nn.Module,
+    device: torch.device,
+    output_path: str,
+):
+    with LilcomChunkyWriter(output_path) as writer:
+        for batch_idx, batch in enumerate(dl):
+            nnet_output = generate_ctc_label_batch(
+                params=params,
+                model=model,
+                batch=batch,
+                device=device,
+            )
+            store_feature_array(
+                nnet_output.cpu().detach().numpy(),
+                writer,
+            )
+
+
+@torch.no_grad()
+def main():
+    parser = get_parser()
+    AishellAsrDataModule.add_arguments(parser)
+    args = parser.parse_args()
+    args.enable_spec_aug = False
+    args.enable_musan = False
+    args.exp_dir = Path(args.exp_dir)
+    args.lang_dir = Path(args.lang_dir)
+
+    params = get_params()
+    params.update(vars(args))
+
+    setup_logger(f"{params.exp_dir}/log-ctc-label/log-decode")
+    logging.info("CTC label generation started")
+    logging.info(params)
+
+    lexicon = Lexicon(params.lang_dir)
+    max_token_id = max(lexicon.tokens)
+    num_classes = max_token_id + 1  # +1 for the blank
+    
+    device = torch.device("cpu")
+    if torch.cuda.is_available():
+        device = torch.device("cuda", 0)
+
+    logging.info(f"device: {device}")
+
+    model = Conformer(
+        num_features=params.feature_dim,
+        nhead=params.nhead,
+        d_model=params.attention_dim,
+        num_classes=num_classes,
+        subsampling_factor=params.subsampling_factor,
+        num_encoder_layers=params.num_encoder_layers,
+        num_decoder_layers=params.num_decoder_layers,
+        vgg_frontend=params.vgg_frontend,
+        use_feat_batchnorm=params.use_feat_batchnorm,
+    )
+
+    if params.avg == 1:
+        load_checkpoint(f"{params.exp_dir}/epoch-{params.epoch}.pt", model)
+    else:
+        start = params.epoch - params.avg + 1
+        filenames = []
+        for i in range(start, params.epoch + 1):
+            if start >= 0:
+                filenames.append(f"{params.exp_dir}/epoch-{i}.pt")
+        logging.info(f"averaging {filenames}")
+        model.to(device)
+        model.load_state_dict(average_checkpoints(filenames, device=device))
+
+    model.to(device)
+    model.eval()
+    num_param = sum([p.numel() for p in model.parameters()])
+    logging.info(f"Number of model parameters: {num_param}")
+
+    aishell = AishellAsrDataModule(args)
+    train_cuts = aishell.train_cuts()
+    train_dl = aishell.train_dataloaders(train_cuts)
+
+    train_sets = ["train"]
+    train_dls = [train_dl]
+
+    for train_set, train_dl in zip(train_sets, train_dls):
+        generate_ctc_label_dataset(
+            dl=train_dl,
+            params=params,
+            model=model,
+            device=device,
+            output_path=os.path.join(args.exp_dir, f"ctc-label-{train_set}.lca"),
+        )
+
+    logging.info("Done!")
+
+
+torch.set_num_threads(1)
+torch.set_num_interop_threads(1)
+
+if __name__ == "__main__":
+    main()