Abstract: Objective To investigate the expression of adhesion molecule CD11c in gastric cancer tissues and the relevance with patients clinicopathologic features and prognosis. Methods The expression of CD11c in tissues from 144 gastric cancer patients，10 gastritis patients and 10 gastric polyp patients was detected by immunohistochemistry. The relationship between CD11c expression and clinicopathologic feature, prognosis of gastric cancer were also analyzed. Results The CD11c expression in gastric cancer tissues was （9.9±6.4）/HPF, significantly higher than （5.1±1.8）/HPF in gastritis and （4.5±2.3）/HPF in gastric polyps tissues. The CD11c expression level in gastric cancer tissues was positively correlated to gender，tumor location，tumor size，depth of invasion，lymph node metastasis，pathological grade and TNM stage，while it was not correlated to age，histological types and recurrence. The median overall survival（OS） of CD11c highly expressed group and lowly expressed group were 67.0 months（95％ CI：39.0-112.0 months）and 29.0 months（95％ CI：21.0-39.0 months） with statistical difference（P＜0.05）. Of gastric cancer patients with stage Ⅲ and Ⅳ, the median OS of CD11c highly expressed group was longer compared with lowly expressed group（P＜0.05）. Cox multivariate analysis showed the CD11c highly expressed group significantly reduced the risk of death compared with lowly expressed group（RR=0.52，95％ CI：0.29-0.94）. Conclusion The CD11c expression level was correlated to the prognosis of gastric cancer，and CD11c can act as an indicator for prognosis of gastric cancer.