The present invention relates to a device for adjusting an angle of a back of an electric-powered bed with an enhanced structure for conveniently performing assembling and adjusting works by adopting a simple configuration of an angle adjustment unit without other special welding work which performs an adjustment work to prevent a maximum rotational angle of the back from exceeding 90°； with respect to a bed frame after the device for adjusting an angle of the back of the electric-powered bed is installed on a bed. The present invention provides the device for adjusting an angle of the back of the electric-powered bed, which has the back rotatable with respect to the bed frame and an angle adjustment unit rotating the back from the bed frame. The angle adjustment unit comprises: a length adjustment screw having one end pin-coupled to a lower bracket arranged at a lower part of the bed frame with a first connection pin, having a screw thread on an outer circumferential surface of the other end, and provided with an adjustment member adjusting the length of the other end going into a hollow space； a connection rod having a hollow space so that the other end of the length adjustment screw is inserted into one end, and the other end into which a connection bracket of an electric-powered cylinder is inserted； the electric-powered cylinder having one side, at which the connection bracket inserted into the other end of the connection rod is formed and supported, and the other side in which a flexible rod member is arranged； and a connection member coupled to an end of the rod member, having left and right sides coupled to be surrounded by back levers arranged at a lower part of the back, and forming a long hole so that a second connection pin, which is pin-coupled to a connection hole of the back lever, is able to be movable left and right.COPYRIGHT KIPO 2018본 발명은 전동식 침대의 등받이 각도조절장치를 침대에 장착한 후에 침대프레임에 대한 등받이의 최대 회전각도가 90°를 초과하지 않도록 조절하는 각도조절수단의 구성을 별도의 용접작업없이 간단한 구성으로 구
