Despite recent advances in the range of therapies available for the treatment of multiple myeloma (MM), there are limited data surrounding survival outcomes and baseline characteristics influencing survival in general clinical practice in Japan. The aim of this study was to use electronic medical records (EMRs) to examine overall survival (OS) and prognostic factors in Japanese patients with MM. We extracted EMRs in the Real World Data (RWD) database of patients with a confirmed diagnosis of MM and treatment history with bortezomib, thalidomide, and/or lenalidomide. OS and prognostic factors for OS were analyzed using a univariate analysis and decision tree model. Of the 6509 patients in the database with a diagnosis of MM, 1565 were eligible. Patients had a median (range) age of 72 (23–92) years, a median OS of 53.5 months, and a 5-year OS rate of 45.6%. In alignment with previous studies, International Staging System stage and age were prognostic of OS. In addition, platelet and erythrocyte counts, chloride, total protein, C-reactive protein, and lactate dehydrogenase levels were identified as important prognostic factors for OS and were used to pilot a simple prognostic tool. In conclusion, we found that the survival outcomes extracted from EMRs in the RWD of Japanese patients with MM aligned with a previous retrospective study from Japan. Baseline laboratory parameters prognostic for OS were explored with additional factors to International Staging System and age identified. These might be used to optimize treatment selection, although further investigation using additional data sources is required.