The present invention discloses a camera imaging method, a camera system and an unmanned aerial vehicle (UAV). The camera imaging method is applied to a camera system of the UAV. The camera system includes a signal trigger device and a signal receiving device. The method includes: acquiring, by the signal trigger device, a shooting instruction; generating, by the signal trigger device, a trigger signal with a preset trigger frame rate according to the shooting instruction; and performing, by the signal receiving device, exposure at the preset trigger frame rate according to the trigger signal; where the preset trigger frame rate is greater than a default exposure frame rate of the signal receiving device. According to the present invention, an exposure frame rate of the signal receiving device is adjusted to the preset trigger frame rate, so that the signal receiving device can perform exposure according to the preset trigger frame rate, and synchronous dual-light exposure is implemented.