An improved dead-beat control algorithm is proposed for the problem that the conventional dead-beat control is actually an one-step-delay control affected by the time delay. The algorithm predicts the active power filter (APF) current reference two sample instants in advance with respect to the measurement instant and the inverter output current one sample instant in advance, and then the “real” dead-beat control is achieved. A mixed prediction strategy is also proposed considering both the steady and dynamic conditions of the load harmonic current, which makes the above prediction process more accurate and more rapid. The simulation experiment shows that the mixed perdition dead-beat control based APF can compensate the harmonic very effective both in the steady and dynamic conditions.