diff --git a/configs/config_all.yaml b/configs/config_all.yaml
index 9de809e78..49dacb6fb 100644
--- a/configs/config_all.yaml
+++ b/configs/config_all.yaml
@@ -255,6 +255,7 @@ process:
       sampling_params: {}                                     # Sampling parameters for text generation. e.g {'temperature': 0.9, 'top_p': 0.95}
   - generate_qa_from_text_mapper:                           # mapper to generate question and answer pairs from text.
       hf_model: 'alibaba-pai/pai-qwen1_5-7b-doc2qa'           # Model name on huggingface to generate question and answer pairs.
+      max_num: null                                           # The max num of returned QA sample for each text. Not limit if it is None.
       output_pattern: null                                    # Regular expression pattern to extract questions and answers from model response.
       enable_vllm: false                                      # Whether to use vllm for inference acceleration.
       model_params: {}                                        # Parameters for initializing the model.
diff --git a/data_juicer/ops/mapper/generate_qa_from_text_mapper.py b/data_juicer/ops/mapper/generate_qa_from_text_mapper.py
index 0f3a1cfef..3113f0f95 100644
--- a/data_juicer/ops/mapper/generate_qa_from_text_mapper.py
+++ b/data_juicer/ops/mapper/generate_qa_from_text_mapper.py
@@ -2,6 +2,7 @@
 from typing import Dict, Optional
 
 from loguru import logger
+from pydantic import PositiveInt
 
 from data_juicer.ops.base_op import OPERATORS, Mapper
 from data_juicer.utils.lazy_loader import LazyLoader
@@ -35,6 +36,7 @@ class GenerateQAFromTextMapper(Mapper):
 
     def __init__(self,
                  hf_model: str = 'alibaba-pai/pai-qwen1_5-7b-doc2qa',
+                 max_num: Optional[PositiveInt] = None,
                  *,
                  output_pattern: Optional[str] = None,
                  enable_vllm: bool = False,
@@ -45,6 +47,8 @@ def __init__(self,
         Initialization method.
 
         :param hf_model: Hugginface model ID.
+        :param max_num: The max num of returned QA sample for each text.
+            Not limit if it is None.
         :param output_pattern: Regular expression pattern to extract
             questions and answers from model response.
         :param enable_vllm: Whether to use vllm for inference acceleration.
@@ -69,6 +73,8 @@ def __init__(self,
 
         super().__init__(**kwargs)
 
+        self.max_num = max_num
+
         if output_pattern is None:
             self.output_pattern = r'Human:(.*?)Assistant:(.*?)(?=Human|$)'  # noqa: E501
         else:
@@ -131,6 +137,10 @@ def process_batched(self, samples, rank=None):
                 output = response[0]['generated_text']
 
             qa_list = self.parse_output(output)
+
+            if self.max_num is not None:
+                qa_list = qa_list[:self.max_num]
+
             if len(qa_list) > 0:
                 for q, a in qa_list:
                     for input_k in input_keys:
diff --git a/tests/ops/mapper/test_generate_qa_from_text_mapper.py b/tests/ops/mapper/test_generate_qa_from_text_mapper.py
index e67285b18..7b3131fd3 100644
--- a/tests/ops/mapper/test_generate_qa_from_text_mapper.py
+++ b/tests/ops/mapper/test_generate_qa_from_text_mapper.py
@@ -19,11 +19,13 @@ def _run_op(self,
                 enable_vllm=False,
                 model_params=None,
                 sampling_params=None,
-                num_proc=1):
+                num_proc=1,
+                max_num=None):
 
         op = GenerateQAFromTextMapper(enable_vllm=enable_vllm,
                                       model_params=model_params,
-                                      sampling_params=sampling_params)
+                                      sampling_params=sampling_params,
+                                      max_num=max_num)
 
         samples = [{
             self.text_key:
@@ -36,6 +38,9 @@ def _run_op(self,
         dataset = Dataset.from_list(samples)
         results = dataset.map(op.process, num_proc=num_proc, with_rank=True)
 
+        if max_num is not None:
+            self.assertLessEqual(len(results), len(samples)*max_num)
+
         for row in results:
             logger.info(row)
             self.assertIn(op.query_key, row)
@@ -45,6 +50,10 @@ def test(self):
         sampling_params = {'max_new_tokens': 200}
         self._run_op(sampling_params=sampling_params)
 
+    def test_max_num(self):
+        sampling_params = {'max_new_tokens': 200}
+        self._run_op(sampling_params=sampling_params, max_num=1)
+
     def test_multi_process(self):
         sampling_params = {'max_new_tokens': 200}
         self._run_op(sampling_params=sampling_params, num_proc=2)