This study was aimed to investigate the normalization of serum free light chain ratio (sPLCR) after treatment of multiple myeloma (MM) and its influence on the prognosis of MM patients. The clinical data of 42 patients with MM were analyzed retrospectively from January 2009 to November 2013 in out department. According to sPLCR consecutive normalization for more 4 weeks or not after treatment, the patients were classified in patients with mormalized sPLCR and patients with abnormalized sPLCR, then the influence of traditional prognostic factors of MM on sPLCR and effect of sPLCR on overall survival (OS) time of MM patients were analyzed. The results showed that the influence of age, ISS stage displayed statistical difference between sFLCR normalization group and abnormalization group, the age ≥ 65 years and ISS stage III negatively impacted on sFLCR normalization (P < 0.05). The response rates of patients with normalized sFLCR were as follows: CR - 60%, VGPR - 38.89%; PR - 28.57%; 17 patients (40.48%) with sFLCR normalization showed superior OS, as compared with patients with sPLCR abnormalization (P < 0.01). It is concluded that the sFLCR normalization is the independent prognostic factor for MM, suggesting that the MM patients with sPLCR normalization after treatment have superior prognosis.