The accident occurred around 11 am at Punnad when a private bus, plying between Mattanur and Iritty, tried to overtake a vehicle and in the process collided with another bus coming in the opposite direction, police said.
The deceased have been identified as Jijo (36) and Suresh (38), drivers of the buses, while the identity of the woman is yet to be ascertained.
The seriously injured were admitted to Pariyaram Co-op Medical College.
Those with minor injuries are undergoing treatment at AKG Memorial Co-op Medical College in Kannur, police said, adding, a case has been registered and investigation is on.