Objective To identify micrometastasis in regional lymph nodes of gastric cancer by quantitative real-time reverse transcription-PCR (qRT-PCR) assay and to evaluate the clinical significance of micrometastasis. Methods To study 320 lymph nodes collected from January 2010 to June 2010， 281 of which were from 40 patients with gastric cancer who had undergone a standard gastrectomy with lymphadenectomy， and other 39 of which were from 10 patients with gastroduodenal ulcer. Made CEA， CK-19， and CK-20 as primers， and used qRT-PCR assay in addition to hematoxylin and eosin staining to detect the micrometastasis， and to analyze the clinicopathologic characteristics.Results Totally， micrometastasis were detected by qRT-PCR assay in 31 (15.34%，31/202) lymph nodes of 28 (70.00%， 28/40) patients. Thirty-nine lymph nodes from 10 patients with gastroduodenal ulcer were negative by qRT-PCR and HE staining. The degree of differentiation， depth of gastric mural invasion， and clinical stage had statistically significant correlation with the incidence of lymph node micrometastasis (P＜0.05). Conclusions qRT-PCR assay is a sensitive and specific method to detect lymph node micrometastasis in gastric cancer patients，and it has importantly clinical significance in evaluating clinical staging，prognosis and treatment prescription.