A casement window with multi-angle window sash includes a window frame (2) and a window sash (5). The window sash (5) is connected with the window frame (2) by a window hinge mechanical structure and a locking mechanism (7), wherein the mechanical structure of the window hinge includes a quadrilateral link mechanism (4), a movable sliding block (10), a gear (9), and a hinge seat (3); the locking mechanism (7) includes a screw rod (75) with an axial plane (78) and a thread (77). The screw rod (75) realizes the locking of the window sash (5) by meshing the thread (77) with the gear (9), and realizes the opening and closing of the window sash (5) by the axial plane (78). The casement window is simple in structure, low in cost, convenient to install and use, and provides high safety.