Open AccessLoss of Heterozygosity (LOH) is commonly considered to be one of a reason when some genes lose their function. Numbers of tumor suppressor genes are existing on the LOH lesion and chromosome 16q24 had been reported as a LOH region in gastric cancer. Little is known about what kind of tumor suppressor genes locates around the position. F-box protein, (FBXO31) is a candidate tumor suppressor gene encoded in chromosome 16q24.3 and LOH of the gene was reported in breast cancer, hepatocellular carcinoma and ovarian cancer but the status of FBXO31 was not analyzed in gastric cancer so far. One hundred twenty-seven pairs of tumor and corresponding normal tissue specimens collected from gastric cancer patients who underwent gastrectomy. Total RNAs were extracted from those samples and the expression of FBXO31 was investigated using real time quantitative RT-PCR analysis. Patients were classified into FBXO31 high expression group and low expression group. Clinicopahological factors were compared between the two groups and importance of FBXO31 was investigated. The standardized expression of FBXO31 was not significantly different between tumor (0.43 ± 0.46) and the corresponding 0.49 ± 0.55 in normal tissue (p = 0.39). Two years survival rate was 77% in FBXO31 high expression group and 54% in low expression group however the chance of survival rate of high expression group was dropped in 5 years (Wilcoxon p = 0.01). Clinicopathological factors were compared between the two groups and peritoneal dissemination was observed significantly higher in FBXO31 low expression group than did in high expression group (p = 0.0398). In order to predict existence of peritoneal dissemination of gastric cancer before surgery, FBXO31 may become a favorite marker for the low risk of peritoneal dissemination.