Abstract: Objective To investigate the expression and clinical significance of Thelperinducing POZ/Krüppel-like factor（Th-POK）CD 4， CD 8， and its related factors RUNX3 and granzyme B（GZMB）in gastric cancer. Methods From March 2011 to October 2014， 100 gastric cancer tissues and adjacent normal tissues were collected. Immunohistochemical PV6000 staining was used to detect Th-POK expression in gastric cancer tissue and normal adjacent tissues， as well as the expression of CD4， CD8， RUNX3 and GZMB protein. The correlation of their expression with clinicopathological features was analyzed. Results The positive expression of Th-POK and CD4 were higher in gastric cancer tissues than those in adjacent normal tissues（80% vs. 67%，P<0.05；77% vs. 60%，P<0.05）. The positive expression of CD8 and RUNX-3 were lower in gastric cancer tissues than those in adjacent normal tissues（80% vs. 60%， P<0.01； 59% vs. 86%，P<0.01）. There was no significant difference of GZMB positive expression rate between gastric cancer tissues and adjacent normal tissue（70% vs. 61%， P>0.05）. The expression of Th-POK and RUNX3 were correlated with TNM stage（P<0.05）， but not with age， tumor site，differentiation and lymph node metastasis（P>0.05）. Th-POK was positively correlated with CD4（r=0200，P<0.05）， and negatively correlated with RUNX3（r=-0373，P<0001）.There was no significant correlation between expression of Th-POK and GZMB or CD8（P>0.05）. Conclusion The expression of Th-POK in gastric cancer tissue is up-regulated， which may interact with RUNX3 to counteract the generation of CD8+ lymphocytes， increases the generation of CD4+ lymphocytes and assists gastric cancer immune escape.