Objective: Elf-1 is a member of the proto-oncogenes Ets-related transcription factor family and over-expressed in many human tumors, Ki-67 is an important nuclear antigen associated with cell proliferation. This study investigated the expression of Elf-1 and Ki-67 in non-small-cell lung cancer(NSCLC) and studied their correlation with the clinicopathological features. Methods: Tissue microarray from 64 cases lung cancer tissue and 10 cases normal lung tissue was constructed, immunohistochemical method was used to evaluate the protein expressions of Elf-1 and Ki-67, correlations of the expression of Elf-1 and Ki-67 to clinicopathological features of NSCLC were analyzed. Results: Expression of Elf-1 and Ki-67 in NSCLC tissues were significantly higher than in normal lung tissues(P < 0.05), the positive rate of Elf-1 and Ki-67 was 73.44% and 64.06% in NSCLC group, Overexpression of Elf-1 in NSCLC was significantly related to histopathological grading, different clinical staging and the intensity of ELF-1 expression was significantly higher in the group with lymph node metastasis than that without(P < 0.05). Overexpression of Ki-67 was also closely related to tumor differentiation, clinical stages and lymph node metastasis(P < 0.05). In addition positive correlation was found between the expressive intensity of Elf-1 and Ki-67(τ = 0.295, P = 0.018). Conclusion: The high expression and positive correlation of Elf-1 and Ki-67 in NSCLC suggest that they probably play a role in onset and progression of lung cancer, united detecting their expression could be used as an valuable molecular biological index for predicting the malignant behavior and early diagnosis of NSCLC. Objective: Elf-1 is a member of the proto-oncogenes Ets-related transcription factor family and over-expressed in many human tumors, Ki-67 is an important nuclear antigen associated with cell proliferation. This study investigated the expression of Elf-1 and Ki-67 in non-small-cell lung cancer (NSCLC) and studied their correlation with the clinicopathological features. Methods: Tissue microarray from 64 cases lung cancer tissue and 10 cases normal lung tissue was constructed, immunohistochemical method was used to evaluate the Results of Expression of Elf-1 and Ki-67 in NSCLC tissues were significantly higher than in The positive rate of Elf-1 and Ki-67 was 73.44% and 64.06% in the NSCLC group, respectively. Overexpression of Elf-1 in NSCLC was significantly related to histopathology grading, different clinical staging and the in The tensity of ELF-1 expression was significantly higher in the group with lymph node metastasis than that without (P <0.05). Overexpression of Ki-67 was also closely related to tumor differentiation, clinical stages and lymph node metastasis (P <0.05). Conclusions: The high expression of the positive correlation between Elf-1 and Ki-67 in NSCLC suggest that it probably play a role in onset and progression of lung cancer, united detecting their expression could be used as an valuable molecular biological index for predicting the malignant behavior and early diagnosis of NSCLC.