Disclosed is an elevator cage comprising a cage platform (1) with several platform sections (2, 3, 4). Stable profiled platform edges (8) are joined to the top faces of all platform sections in order to stabilize the entire cage platform. The platform sections are also provided with joining points (2.1, 3.1, 4.1) which are located on parallel vertical planes and at which the platform sections are additionally interconnected by means of joining elements. According to the inventive method for installing an elevator, the cage platform (1; 21) is prepared in the production facility in at least two separate platform sections (2, 3, 4) and is delivered to the place of installation of the elevator along with two profiled platform edges. The separate platform sections (2, 3, 4; 22, 23, 24) of the cage platform (1; 21) and the profiled platform edges are joined together by means of joining elements at the place of installation so as to form a cage platform.