An electric bed frame includes a retaining frame, a back supporting frame pivotally connected to the retaining frame, a thigh supporting frame having a front end pivotally connected to the retaining frame, a lower leg supporting frame having a front end pivotally connected to a rear end of the thigh supporting frame, and a first link rod having a front end pivotally connected to the thigh supporting frame, and a rear end slidably disposed in a slide coupling part of the retaining frame. An actuator has two ends pivotally connected to the back supporting frame and the retaining frame, respectively. A linking member has a front end connected to the actuator or a pushing member of the back supporting frame, and a rear end connected to the first link rod.
