In order to get photodisruption threshold of porcine nasopharynx tissue in nasopharynged carcinoma optical biopsy, temperature distributions in the porcine nasopharynx tissue were measured under irradiation of argon ion laser at the wavelength of 488 nm and 514.5 nm, respectively. The dependence of the temperature distribution on the measuring position and irradiation power density, as well as wavelength was studied in detail. Experimental results show that the temperature distributions in the porcine nasopharynx tissue were significantly affected by measuring position and the power density, as well as wavelength of irradiation laser. The temperature in the porcine nasopharynx tissue is increased with the increasing of the power density of irradiation laser, and the maximal temperature can be higher than 41.5℃ when the power density reaches 1.85 W/cm2. The optical-thermal effect at the wavelength of 514.5 nm is more remarkable than that of 488 nm under the irradiation of same power density.