Abstract: Objective : To detect mRNA and protein expression of MICA in Tibetan patients with gastric cancer at plateau of Qinghai and to explore its significance. Methodse : The expression of MICA mRNA and MICA protein was detected in 33 gastric cancer tissues and adjacent non-cancerous tissues of Tibetan patients. Spearman rank correlation was used to analyze the correlation between them. Results : The mRNA and proteins levels of MICA were significantly higher in gastric cancer tissues than in adjacent non-cancerous tissues,with a significant difference among the well differentiated cases, moderately differentiated cases and poor differentied cases (P<0.05). Spearman rank correlation analysis revealed that the expression of MICA mRNA was positively correlated with MICA protein expression (r s =0.903, P<0.01). Conclusion : The overexpression of MICA may play an important role in the occurrence and development of gastric cancer in Tibetan patients at plateau of Qinghai. The increase of MICA mRNA expression is closely correlated with that of MICA protein expression in gastric cancer.