Bed with a desk function is started. The bed having a desk functions of the present invention, the plurality of bed frame forming the framework of the polygon, the headboard is provided on one side of the bed frame and is provided inside the space formed by the bed frame and constituting the floor base plate, the It includes a mattress that is placed on the upper surface of the bottom plate, and wherein is the facing position of the bed frame installed, each with a pair of rails, the bottom plate is configured, each divided into a movable separate from the stationary plate board on which the moving plate is installed and the ball is formed through between each of the fixing plate of the position, in the state mattress is spread on the bottom plate is configured to function as the bed, folding the mattress and keep it in the upper surface of the fixed plate, the moving plate between each of the fixed plate after the separation by the fixed rails on each, the user characterized in that to make use of the mobile plate on the fixed plate put astride the bridge on the through-hole to the desk top. The present invention provides an effect that the user to separate the moving plate from the bottom plate support placed on rails and, sitting by a through hole astride the fixed plate may also be used as a bed by being able access to the moving plate by Desk being able to, by that the user can be folded mattress while sitting down on the fixed plate to the "b" shape used as a cushion for supporting the backrest portion and the buttocks are supported on the headboard, it is possible to provide convenience to the user.