Abstract Direct borohydride fuel cells (DBFC) are considered as attractive energy suppliers because of their high electrochemical activity, open circuit potential, energy storage capacity, and power performance at ambient temperature. For the successful commercialization of the DBFCs, cost effective and high performance cells should be produced. In this study, the analysis and optimization of the DBFC operation conditions are carried out with Design Expert software central composite tool. Power density is chosen as a response (dependent) parameter and cell temperature, borohydride concentration, anode and cathode flow rates and catalyst loading are chosen as independent parameters. Based on ANOVA (analysis of variance) analyses, the maximum power density of 108.5 mW cm −2 is obtained at cell temperature of 79.8 °C, borohydride concentration of 1.5 M, anode flow rate of 5 cm 3 min −1 , cathode flow rate of 0.1 dm 3 min −1 and PtRu/C catalyst loading of 0.7 mg cm −2 .