Objective To examine the protein expression of Ras-association domain family 10 (RASSF10) in human gastric cancer and its association with clinicopathological parameters of prognosis in patients with gastric cancer. Methods A total of 105 gastric cancer specimens were collected in Changzheng Hospital, Second Military Medical University from Jan. 2008 to Dec. 2010. All patients had detailed clinicopathological data and were followed up for at least 5 years or till they were dead. Immunohistochemical (IHC) analysis was performed to detect RASSF10 expression in gastric carcinoma and adjacent normal tissues. The correlations between RASSF10 expression and clinicopathological factors, and patients' prognosis were evaluated through statistical analysis. Results The IHC results revealed that negative expression of RASSF10 was observed in 61.9% (65/105) of gastric cancer patients. The level of RASSF10 was significantly associated with the tumor size, pathological grade, pathological type, T stage and lymph node metastasis (all P<0.05), but not correlated with age, gender, tumor site, distant metastasis or AJCC staging (all P>0.05). Kaplan-Meier curve showed that negative expression of RASSF10 predicted significantly worsened prognosis of gastric cancer (P<0.05). Multivariate Cox regression analysis indicated that RASSF10 expression (HR=0.528, P=0.041) and AJCC stage (HR=4.994, P=0.001) were independent prognostic factors for the survival of gastric cancer patients. Conclusion RASSF10 protein is down-regulated in gastric cancer tissues and is associated with a poor prognosis of gastric cancer, which indicates that RASSF10 may serve as a potential prognostic biomarker for gastric cancer.