The invention discloses a mattress capable of preventing pressure sores. The mattress comprises a mattress body, wherein a capsule body made of rubber is disposed on the upper surface of the mattress body; a film made of a waterproof and breathable material is disposed on the inner wall of the capsule body; the capsule body is filled with water; vent holes are formed in the capsule body wall; a repeatedly bent self-oscillation flow heat pipe is disposed inside the mattress body near the upper surface; an evaporator is disposed on one side of the self-oscillation flow heat pipe, and a condenser is disposed on the other side; multiple cavity-shaped net frames are disposed inside the self-oscillation flow heat pipe along the pipeline extending direction; and fixed particles are disposed in the net frame. The mattress capable of preventing the pressure sores with the structure has the advantages of the simple structure, low cost, good heat dissipation effects and good massage functions.