Abstract: The major problem of traditional direction-of-arrival (DOA) estimation algorithms based on subspace-divided method is that it requires massive calculations and cannot be applied on arbitrary array structures.Based on an actual hemisphere conformal array, several search-free algorithms which can be applied on arbitrary arrays are studied.The performances of these algorithms on conformal antenna array are compared.Theoretic analysis and numerical simulations show that these algorithms can achieve good performance on conformal array under certain conditions.