Abstract: ob＜x＞jective To analyze the data of prealbumin, platelet before treatment in extensive stage small cell lung cancer (SCLC) patients, and explore its prognostic value for patients with extensive-stage estimate small cell lung cancer. Methods This study?retrospectively analyzed 116 Patients with SCLC in the department?ofRespirtory Medicine in the Affiliated Hospital of Xuzhou Medical University from February 2012 ?to? July 201 7，who accepted the standardized EP chemotherapy. The reason of the death is the tumor. Excluding the impact of gender, age, comorbidities, ECOG score, the relationship between prealbumin and platelet ratio and patients’PFS and OS ?was?analyzed with Kaplan-Meier method and Cox?scale risk model. Results Prealbumin level before treatment in patients with PFS was significantly associated (P = 0.013), and significantly associated with the patients’ OS ( P = 0.025). Platelet before treatment was not significantly associated ( P = 0.093), but was significantly associated with the patients’ OS ( P = 0.026). Conclusion: The prealbumin and platelet before treatment was associated with the prognosis of extensive stage small cell lung cancer.