According to explosive-determination of power-lead block method and the power of three powdery pyrotechnics such as fulminating powder, red powder and black powder were studied through the method of ignition, the temperature of lead block and the type of pyrotechnics. Results show that pyrotechnics can be detonated through electric detonator, when density of charge is less than or equal to 1.047g?cm-³. The lead temperature needs to be corrected in order to compare the power of pyrotechnics. The power of fulminating powder is the maximum of 113.29mL, and the powers of red powder and black powder are 51.20 mL and 51.60 mL, respectively.