This paper proposes a leader-follower formation control with integrated collision avoidance. First, a constrained unmanned aerial vehicle (UAV) swarm model is constructed based on a leader–follower framework. Based on this framework, a formation controller based on the consensus algorithm is designed to achieve both formation maintenance and transformation. For autonomous collision avoidance, for the leader UAV, the interfered fluid dynamics system (IFDS) is proposed; for the follower UAVs, the threat assessment based on speed obstacle angle is proposed, and then formation transformation based on consensus algorithm is used to achieve collision avoidance. Simulations are carried out to demonstrate the effectiveness of the algorithm.