The utility model discloses a high -voltage electronic firing circuit and oxygen bomb calorimeter, wherein the former includes: DC power supply, ignition switch, self -maintained circuit, high -pressure energy storage circuit, self discharge circuit and two ignitor electrodes, self -maintained circuit includes triode and first transformer, and high -pressure energy storage circuit includes energy storage electric capacity, diode and the second transformer, and the self discharge circuit includes time delay electric capacity, silicon controlled rectifier and slide rheostat, and the both ends at the second transformer's secondary coil are connected respectively to the ignitor electrode. Through the technical scheme of the utility model, improve ignition's reuse rate, improved the success rate of igniteing, reduced manual operation's process to user's the use experience and the accuracy and efficiency of measurement experiment device process have been promoted.