Elastic strain energy of a free-standing body with many inclusions was calculated. In order to consider the effect of surrounding neighborhood inclusions, nonlocal terms of the Green's function were kept. The calculated strain energy by a derived analytic method was compared with that of the finite element method. The prediction of the new analytic method provided a correct tendency of the variation of the strain energy for various sample problems. Deviation of the analytic result from that of the finite element calculation became smaller when the value of the strain energy decreased. As the analytic method does not require solving the field equations, it can be useful for a situation demanding prompt computation of the strain energy. (C) 2012 Elsevier Ltd. All rights reserved.