In this paper, the binary Bell polynomials are employed to find the bilinear form, bilinear Backlund transformation and Lax pair for the (3+1)-dimensional BKP equation. Based on Hirota's bilinear form and three-wave method, multi-soliton solutions are presented. Furthermore, a new bilinear Backlund transformation is constructed via applying a gauge transformation to the Backlund transformation in bilinear form.