An elevator control of a one-shaft multicar system includes: a collision predictor predicting occurrence of a collision of cars against each other in a same shaft in a case a predetermined collision prediction implementation condition is held; a waiting-with-door-open determination mechanism determining whether or not a car is caused to be on standby with the door thereof kept open in a case the collision predictor predicts the collision of cars against each other in the same shaft; a waiting-with-door-open floor determination mechanism determining a waiting-with-door-open floor of the car in a case the waiting-with-door-open determination mechanism determines the car is caused to be on standby with the door thereof kept open; and a controller causing at least either of the cars, for which occurrence of a collision is predicted, to be on standby with the door thereof kept open at the waiting-with-door-open floor determined by the waiting-with-door-open floor determination mechanism.