We examine the radiation-induced properties changes of evanescent-field-interacting type graphene-saturable absorbers (SAs). The graphene-SA inserted to the mode-locked laser was exposed to 60Co gamma-ray radiation up to 1.02 kGy at a 50 Gy/hr dose rate. To see how the graphene-SA affects to the laser performance, the graphene-SA-based mode-locked laser was so monitored simultaneously. The mode-locking was broken at 0.75 kGy irradiation dose, which corresponds to 15.6 years operation in low-earth orbit satellites. The optic properties of the graphene-SA was so compared before and after radiation.