Aiming at the mapping requirements of forestry, architecture, offshore, island reef and beach, the Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, has developed a prototype of airborne dual-frequency laser radar. It can simultaneously carry out mapping of terrain and submarine terrain. The prototype has been tested in Wuzizhou Island of Sanya with a maximum detection depth of 30 m, equivalent to 50 m under class A water quality conditions, the minimum detection depth of 0.22 m. Depth data and single-beam sonar data comparison error is 0.108 m, ranging data and field-measured data comparison error is 0.18 m. The results are in accordance with the design expectations.