Preheating characteristics of hydrogen peroxide monopropellant thruster with manganese oxide catalyst were investigated. Monopropellant thruster requires to preheat a catalyst bed for efficient operation in space environment. Optimum preheating temperature of hydrazine monopropellant thruster was well studied. However, preheating characteristics of 90 wt% hydrogen peroxide monopropellant thruster with manganese oxide catalyst are still a subject to research. For this purpose, a 50 N vacuum thrust class monopropellant thruster was employed. The preheating temperature was from 50 degrees C to 250 degrees C in increments of 50 degrees C, and a test in cold start was included as a control group. Their preheating characteristics were expressed in terms of rising time and pressure instability. The results indicate that a significant improvement in rising time and pressure instability was observed until the preheating temperature reached 150 degrees C. However, in further preheating temperature, the results showed no noteworthy improvements. (C) 2014 Elsevier Masson SAS. All rights reserved.