Abstract: A new fast difference iterative solution model is proposed to adjust parameters of surveying and mapping by least-squares method with multi-type, multi-precision, multi-source dynamic and nonlinear data in digitalized construction, which can avoid computing derivative completely and reduce calculation of Jacobi matrix. At the same time, a matrix sequence, which can approximately substitute for second-order partial derivative matrix by recurrence method, is constituted to make the rate of convergence of the algorithm model faster. This creates a new solution to solve the generalized nonlinear least squares adjustment of surveying and mapping by parameters.