Abstract: The raw data acquired in beyond-visual-range (BVR) air combat is not accurate and contains incomplete information. Existing situation assessment methods cannot reflect the impact of fighter maneuvering, which makes the credibility not reliable. The interval set pair analysis (SPA) is used to handle the BVR situation assessment. The feasibility of SPA handling is analyzed with the evidence theory. The fighter maneuvering is taken into account to construct an interval decision-making matrix by calculating the situation in a certain period of time. The interval numbers are transformed into connection numbers and the weights are optimized with particle swarm optimization (PSO). It is verified that the authenticity of the situation assessment is improved to a certain extent.