Provided is a heart rate activity detecting method based on dynamic images. The method includes tracking a moving object. Preset brightness is determined based on an ambient condition. An image of the moving object is captured to generate a corresponding RGB color space, which is then converted to an image color space with adjustable brightness. The brightness of the image color space is adjusted according to the preset brightness to generate an image with corrected brightness, which is then converted to a RGB color space with the corrected brightness for calculating a heart rate activity of the moving object. The disclosure is capable of addressing the issue of an unstable light source by adjusting the brightness of the dynamic images, and then calculating the heart rate activity of the moving object according to the dynamic images. A heart rate activity detecting system based on dynamic images is also provided.
