Time of arrival (TOA) data association is a key technology in multiple illuminators and the single receiver based non-cooperative detect systems. To solve the problem that the permutation and combination in the traditional algorithms result in a high computational cost, this paper proposes a TOA data association algorithm based on the reconnaissance region searching. Firstly, some samples of the TOA curves can be obtained by azimuth searching, and then the data association problem can be transformed into a 2-dimensional detection problem by blurring and adding the curves. The simulation results show that the proposed algorithm can improve the computational efficiency with hardly reduction of the correct association probabilities, implying good application prospect.