The invention discloses a composite multifunctional nursing bed. The composite multifunctional nursing bed comprises a seat body part, a left bed body, a right bed body and a nursing device. The seat body comprises a main backboard, a seat board, a leg plate, a foot plate and corner motor assemblies. The main backboard, the seat board and the leg plate are connected through the corner motor assemblies. The left side bed body and the right side bed body are each composed of a transformable bed frame, a side turning baffle auxiliary motion mechanism, an armrest frame, a foot board supporting mechanism and a rotary shaft assembly. The left bed body and the right bed body have the main effects of supporting a bed body and providing power for side turning of the bed body. The rotary shaft assemblies are dynamically connected with the left bed body and the right bed body through electric push rods, and side turning of the bed body and bed and chair separating are achieved. The corner motor assemblies are composed of direct current motor sets and connecting parts. Back lifting, leg bending, sitting posture adjusting, side turning and separation of the bed and a chair can be achieved, the problem of defecation and urination of a nursed person is solved, and the advantages of being complete in function, high in integration degree, high in practicality and the like are achieved.