The invention discloses a ventilation device for an elevator car, relates to the field of elevator cars and aims to solve the technical problem that since a conventional elevator car with an air-conditioning system is generally closed, ventilation is slow, air inside the elevator car cannot be fully exchanged when the ambient temperature does not reach an air conditioner starting range, and consequently, passengers feel uncomfortable. The technical scheme that ventilation holes are formed in side walls of the elevator car, and ventilation mechanisms are arranged corresponding to the ventilation holes is adopted. The ventilation holes in the side walls of the elevator car work together with the ventilation mechanisms, and wind power generated when the elevator car runs up and down is utilized to change air inside the elevator car, so that the problem of poor ventilation and permeability of a closed elevator car is effectively solved. The ventilation holes can be opened or closed according to a signal of a temperature sensor arranged in the elevator car, so that the cost is further reduced.