In this paper, interleaved LLC half-bridge resonant converters are designed and implemented. In order to increase output power, two LLC resonant converters are parallel-connected. The gate driver signals of two LLC converters are interleaved by 90˚ to reduce output-current ripple. Besides, switch losses on power devices can be reduced by zero voltage switching(ZVS) and zero current switching (ZCS) on output diodes. The characteristics of the proposed topology are discussed, and the operation principles and control circuit design are also addressed in this paper. Finally, interleaved LLC half-bridge resonant converters with input 380~420 V and output 24 V/20 A is implemented to verify the theoretical feasibility.