Abstract: A method for accessible domains calculation and its three-dimensional visualization is proposed in this paper, aiming at the shortage in accessibility analysis functions of the related simulation software when developing virtual maintenance in the case of using maintenance tools. Firstly, the size of virtual human's arm is computed according to its configuration structures. Secondly, a technique to calculate the farthest accessible distance is given with the information of tools' remote node point. The magnified scale is calculated by the distance value and the length of the virtual human's arm, and then the scale is utilized to realize visualization for the accessible domain when use the maintenance tools. Finally, the accessibility analysis function mentioned above is implemented based on the Jack software with Tcl/Tk and Python programming languages. The simulation examples show that the proposed approaches satisfy the accessibility analysis in the case of using maintenance tools, and the automatic function that generates simulation reports will lower the burden of simulation personnel.