Abstract: Based on measuring the movement of lasing wavelength closed to the substrate while injected different duty cycle current,the mu ltiple active regions high-power laser's thermal resistance was calculated.Compared with traditional laser diodes,the novel laser's thermal resistance increases with the number of active region.Because the series resistance of novel dual-wavelength laser diodes is lower than the sum of two tradition al laser diodes series resistance,the novel laser's thermal resistance is also lower than the sum of two traditional laser diodes thermal resistance.