With petroleum ether and acetone as mixed solvents, the photoisomerization of norbornadiene to quadricyclane was studied, including the influences of initial concentration, amount and type of photosensitizer and reaction time. The optimal reaction conditions were obtained as follows: room temperature, initial reaction concentration 1.0 mol·L^-1, 6% benzophenone, ultraviolet radiation 15 h, which make norbornadine′s conversion up to 93% and selectivity of 100%. After vacuum distillation, high purity quadricyclane fuel (95% purity) was gained with 73% isolated yield.