A set of high explosive pumped photolytic iodine laser system was built and a steady laser output of approximate 100 J was obtained in experiments. The radiation spectra of shock wave produced by high explosive in argon of about 101.325 kPa were measured, meantime the velocities of shock wave were also measured by photography. In the experiments, the alkyl iodine C3F7I was used as laser working substance and a good waveform of laser was obtained. The full width at half maximum (FWHM) of laser pulse is about 34 μs and minimum angle of radiation is less than 20 mrad. The principle and technique routines were introduced in the paper. The experiments under different conditions were carried out and the expenimental results were listed and analyzed. The factors that influence the laser output had been discussed. This technique progress made it possible for making a larger energy explosive-driven iodine photodissociation laser.