Carrier phase double difference GNSS spoofing detection technique is an effective one of those methods based on phase measurement, but the high false alarm probability problem is caused by angle ambiguity for double-element antenna-array. Therefore, a technique based on antenna-array direction change was presented. The carrier phase double differences were estimated in different antenna-array directions, and then the carrier phase double differences were used to discriminate the spoofing signals. In this way, the angle ambiguity can be eliminated, and the false alarm probability was reduced. Simulation results verified the effectiveness of the proposed spoofing detection technique.