The utility model discloses a data recorder for lake biological investigation. The computer case comprises a host case body, a strap is mounted on the side edge of the mainframe box body through an upper buckle; a solar cell panel is installed at the upper end of the mainframe box body. Wherein a display screen and a keyboard are mounted on the mainframe box body; a heat dissipation opening is formed in the side edge; the lower end of the mainframe box body is connected with the outer shell through a fixing piece and a positioning groove. The upper buckle is connected with the lower buckle ina clamped mode through a first clamping piece and a second clamping piece, the lower buckle is connected with a fixing buckle through a connecting belt, a second partition plate is arranged in the outer shell, a storage battery and a push-pull box are arranged at the upper end and the lower end of the second partition plate respectively, and a first partition plate is installed on the inner side of the push-pull box. According to the data recorder for lake biological investigation, the field cruising ability can be improved through the solar cell panel and the storage battery, the data recorder can be conveniently disassembled, and meanwhile samples can be conveniently collected.