A double-integrating-spheres system, basic principle of measuring technology of ray radiation, optical model of biological tissues were used for the study. Optical properties of human normal bladder and bladder cancer tissues at 532 nm and 808 nm laser and their linearly polarized laser irradiation were studied. The results of measurement showed that attenuation of light intensities in human bladder cancer tissue were obviously bigger than one of human normal bladder tissue at a certain wavelength of laser or the linearly polarized laser irradiation. Attenuation of light intensities in human bladder cancer tissue at 532 nm and 808 nm laser was slightly bigger than one of human normal bladder tissue at the linearly polarized laser irradiation. Attenuation of light intensities in human bladder cancer tissue at 532 nm and 808 nm laser and their linearly polarized laser irradiation was obviously bigger than one of human normal bladder tissue at 532 nm and 808 nm laser and their linearly polarized laser irradiation. Refractive index of human normal bladder or human bladder cancer tissue at a certain wavelength of laser and its linearly polarized laser irradiation had not obvious distinction. Refractive index of human normal bladder tissue was obviously bigger than one of human normal bladder tissue at 532 nm and 808 nm laser. Optical properties of all of human normal bladder tissue and bladder cancer tissues in Kubelka-Munk two-flux model at a certain wavelength of laser or its linearly polarized laser irradiation had prominent distinction (P＜0.01). Optical properties of a certain of tissue at 532 nm and 808 nm laser and their linearly polarized laser irradiation had either prominent distinction (P＜0.01). Optical properties of human normal bladder tissue at a certain wavelength of laser and its linearly polarized laser had obvious distinction. And optical properties of human bladder cancer tissue at a certain wavelength of laser and its linearly polarized laser irradiation had not prominent distinction. Attenuation of all of the forward scattered photon fluxes i(x), the backward scattered photon fluxes j(x), the total scattered photon fluxes I(x) of human bladder cancer tissue at 532 nm and 808 nm laser and their linearly polarized laser irradiation is obviously bigger than one of human normal bladder tissue. And that light intensities of their forward scattered photon fluxes i(x) was obviously bigger than one of their backward scattered photon fluxes j(x).