The purpose of present study is to determine and compare the optical properties of normal human pulmonary artery tissue in vitro at 650, 680, 710, 740, 780 nm wavelengths of Ti:Sapphire laser. The optical parameters of tissue samples were determined using a double integrating sphere set-up. The inverse Adding-doubling method was used to determine the optical properties from the measurements. The results of measurement showed that the absorption coefficients for pulmonary arteries increase with increase of laser wavelength, the maximum absorption coefficient is 0.277 mm-1 at 780 nm, and the minimum absorption coefficient is 0.160 mm-1 at 650nm, and the reduced scattering coefficients for pulmonary arteries increase with decrease of laser wavelength, the maximum reduced scattering coefficient is 48.8 mm-1 at 650 urn, and the minimum reduced scattering coefficient is 13.3 mm-1 at 780 nm. The optical penetration depths for pulmonary arteries increase with increase of laser wavelength, the maximum optical penetration depth is 0.298 mm at 780 nm, and the minimum optical penetration depth is 0.206 mm at 650 nm. The backscattered reflectances for normal human pulmonary arteries increase with decrease of laser wavelength, the maximum backscattered reflectance is 0.794 at 650 nm, and the minimum backscattered reflectance is 0.561 at 780 nm.