The high-resolution absorption spectra of real atmosphere near the 1.315 μm wavelength were recorded accurately using an experimental system. The system includes a tunable narrow-line-width pulsed ΟΡΟ laser, a multipass absorption cell of the White-type with total optical length as long as 1097 m, and a single time-division multiplexing fast-response detector system. It is verified from the spectra that water vapor is the main absorption gas in the wavelength band. The absorption cross-section of atmospheric absorption molecule at the wavelength of iodine laser (7603.14 cm-1) was gotten from the measurement data which is (1.05±0.09)×10^{-24} cm2 (at the standard atmospheric condition). And the parameters of atmospheric absorption lines were also obtained around the wavelength of 1. 315 μm from the measured spectra. The absorption cross — sections of atmospheric absorption molecule near the wavelength of iodine laser were also calculated from the measurement parameters.