The invention discloses a sample processing device adopting angle drilling core test horizontal crustal stress. The device comprises a core fixture arranged on a rock sample drilling rig, the core fixture comprises a hydraulic enclasping component, an angle support bracket and an enclasping fixing bracket; the angle support bracket is fixedly arranged on a drilling jig working table below a sampling drill bit of the rock sample drilling rig, the hydraulic enclasping component is installed on the angle support bracket through the enclasping fixing bracket, the hydraulic enclasping component fixes and enclasps the two ends of an angle drilling core and is locked and positioned relative to the enclasping fixing bracket, one end of the enclasping fixing bracket is hinged, and the other end ofthe enclasping fixing bracket and the angle support bracket are fixed in an adjustable mode. Accordingly, the core is enclasped and fixed by the hydraulic enclasping component, compared with an existing manual mixing mode, the device has the advantages of being accurate in angle setting, good in sample fixing, capable of saving labor and easy to operate, horizontal crustal stress measurement is accurately conducted on angle drilling core sampling, and basic meaning on design of construction safety of geotechnical engineering is achieved.