The invention mainly belongs to the technical field of metal pressure machining, and particularly relates to a thickness control method of an aluminum plate hot mill adopting electric and hydraulic screwing down. The thickness control method comprises the steps that firstly, the rolling force of the last two passes is set to be close, after rolling of the last but one pass is completed, a roll gap is kept unchanged, the electric screwing down bounce amount, the average roll gap and the average rolling force in the rolling process of the pass are calculated, and the average rolling force is used as the target rolling force of the last pass; then, in combination with manual measurement thickness, a target roll gap and a pre-swing roll gap before biting of the last pass are calculated, and a screwing down mechanism achieves execution in place; and in the rolling process of the last pass, through comparison of the actual rolling force and the target rolling force and deviation of the actual roll gap and the target roll gap, the outlet thickness deviation is calculated in real time in combination with a bounce equation, closed-loop control is put in, and therefore thickness precision is guaranteed. According to the thickness control method, under the condition of not depending on a thickness gauge, the thickness of the single-rack aluminum plate hot mill adopting electric and hydraulic screwing down can be precisely controlled.