The present invention discloses a transformable yo-yo, comprising two rotators and a connecting shaft, wherein a though hole, into which the connecting shaft is inserted from two directions, is provided in the middle of each of the rotators, and a connecting device, configured to connect and secure the connecting shaft, is provided in the through hole; by moving the connecting device, the securing to the connecting shaft can be released so that the rotators are separated from the connecting shaft; the back sides of the two rotators are oppositely connected to the connecting shaft, and connected and secured through the connecting device to assemble a yo-yo of a first form; and after releasing the securing, the front sides of the two rotators are oppositely connected to the connecting shaft, and secured through the connecting device as well to assemble a yo-yo of a second form. Kids can transform a yo-yo to a different form according to their preferences, and the yo-yo in a different form also has different characteristics. As the characteristics are different, different tricky moves are possible. Kids may play with a yo-yo in more varied ways and have more fun. The transformable yo-yo of the present invention, which is an equivalence to two existing yo-yos, is more cost effective and can gain traction more easily among with kids.