〔Abstract〕 Objective To investigate the expression, clinical significance and correlation with cell cycle related proteins c-myc and CDC25 A of TRIM59 in non-small cell lung cancer(NSCLC). Methods 40 cases with NSCLC tissues(NSCLC group) and 40 cases with normal lung tissues(normal group) were selected and the expression levels of TRIM59 mRNA in two groups were detected by reverse-transcription polymerase chain reaction(RT-PCR). The expressions of TRIM59, c-myc,and CDC25 A in these two groups were detected by immunohistochemistry. Meanwhile, clinical data of the patients were collected to analyze the correlation between TRIM59, c-myc,and CDC25 A expression and the clinical pathologic features. The correlation among the three proteins were analyzed by spearman test. The survival curve was drawed to analyze the correlation between TRIM59 and the prognosis of NSCLC patients, and Cox regression model was established to analyze the prognostic factors of NSCLC patients. Results RT-PCR showed that the expression level of TRIM59 mRNA(0.87±0.14) in the NSCLC group was significantly higher than that in the normal group(0.16±0.05)(t=2.901,P=0.002). Immunohistochemistry showed that the expression levels of TRIM59, c-myc and CDC25 A in the NSCLC group(72.50%, 67.50%, 60.00%) were significantly higher than those in the normal group(15.00%, 10.00%, 17.50%)(allP=0.000). The expression levels of TRIM59, c-myc and CDC25 A in the NSCLC group were all correlated with the degree of lesion differentiation, TNM stage, vascular invasion, lymph node metastasis and liver metastasis(allP<0.05), but not related to age and gender(allP>0.05). Spearmen correlation analysis showed that TRIM59 was significantly correlated with c-myc and CDC25 A in the NSCLC group(r=0.451,P=0.000;r=0.421,P=0.002). Survival analysis showed that the survival time of NSCLC patients with TRIM59 positive expression was significantly shorter than that of NSCLC patients with TRIM59 negative expression(P<0.05). Cox regression model confirmed that TRIM59 expression was an independent prognostic factor of NSCLC patients. Conclusion The high expression of TRIM59 plays an important role in the occurrence and development of NSCLC, which is considered to be related to the up-regulation of cell cyclin-related proteins c-myc and CDC25 A.TRIM59 can be used as a potential biological indicator for the early diagnosis and prognosis monitoring of NSCLC.