In this paper, two (3 + 1)-dimensional nonlinear evolution equations (NLEEs) are under investigation by employing the Hirota's method and symbolic computation. We derive the bilinear form and bilinear Backlund transformation (BT) for the two NLEEs. Based on the bilinear form, we obtain the multi-soliton solutions for them. Furthermore, multi-soliton solutions in terms of Wronskian determinant for the first NLEE are constructed, whose validity is verified through direct substitution into the bilinear equations.