A digital microfluidic chip and a digital microfluidic system. The digital microfluidic chip comprises: an upper substrate and a lower substrate arranged opposite to each other; multiple driving circuits and multiple addressing circuits disposed between the lower substrate and the upper substrate; and a control circuit, electrically connected to the driving circuits and the addressing circuits. The control circuit is configured to apply, in a driving stage, a driving voltage to each driving circuit, such that a droplet is controlled to move inside a droplet accommodation space according to a set path, measure, in a detection stage, after a bias voltage is applied to each addressing circuit, a charge loss amount of each addressing circuit, and to determine the position of the droplet according to the charge loss amount. The charge loss amount of each addressing circuit is related to the intensity of received external light.