An outdoor unit for an air conditioner, and an air conditioner are provided. The outdoor unit has a housing and a draught fan. The housing is provided with a first air exchange port and a second air exchange port. The draught fan is arranged in the housing and located between the first air exchange port and the second air exchange port. The draught fan has an electric motor, a first fan, and a second fan. The electric motor has two rotors which rotate independently of each other, and a first output shaft and a second output shaft connected to the two rotors respectively. The first output shaft and the second output shaft are respectively fixedly connected to the first fan and the second fan for driving the first fan and the second fan to rotate independently of each other.