Atmospheric pressure is one of the most important meteorological parameters. In this work, to realize spaceborne laser remote sensing of atmospheric pressure, ground-based lidar measurement investigations are conducted. A 532-nm laser pulse produced by the second-frequency of a single longitudinal-mode Nd∶YAG laser is used as a pump source. An optical parametric oscillator and an optical parametric amplifier using a KTP (KTiOPO4) crystal as a nonlinear conversion medium generate two laser pulses with wavelengths of 760.236 and 760.307 nm, with the pulse energy reaching 40 mJ. A ?350-mm telescope receives the backscattering of the atmosphere, the differential optical depth of two wavelengths between different altitudes and the lidar is obtained. The effective detection altitudes range of the ground-based differential absorption lidar is 500--4000 m, and the time resolution is 1--5 min. The investigations show that the differential optical depth corresponds to the pressure difference between different altitudes of the atmosphere and the lidar, and a numerical expression of the corresponding relationship can be obtained.