Background: Pemetrexed (PEM) is effective in first-line treatment for patients with non-squamous non-small cell lung cancer (NSCLC). However there are currently no definitive determinants to certify which patients could benefit from PEM. To improve the efficacy of PEM combined with platinum as first-line therapy for advanced non-squamous NSCLC, we conducted this retrospective study to detect potential determinants of this regimen. Methods: We recruited 109 patients with advanced non-squamous NSCLC who received PEM with a platinum as first-line therapy from June 2006 to February 2013 in Jiangsu Cancer Hospital. Multiple variables (age, sex, smoking, degree of cell differentiation, hemoglobin, platinum drugs combined, positions of metastasis) were selected. Logistic regression analysis was used to analyse relationships between these variables and tumor response. Result: In univariate analysis, we found that age and platinum significantly influenced the results of PEM therapy (P<0.05). In multivariable analysis, no factors were independently significant. Conclusion: Our analysis did not suggest that the age, sex, metastasis of liver or other organs, hemoglobin, smoking history and pathological differentiation are associated with the response of PEM. We should conduct further analyses with larger sample size to reconfirm this issue.