In this paper we provide a neighbor finding algorithms for three-dimensional objects modeling represented by octants. First, Cixy' lyz , and C lxz' the stereographic projections of the object modeling C on the XY,YZ,and XZ planes, are found respectively. C1xylxz' Ctxzlyz, the stereographic projections of Clxy' lyz' and Clxz on the XZ,XY, and YZ planes, are found respectively. Each octants constructing C are levelized in a specified direction. The octants associated with same level number are grouped together. Each groups of octants are ordered in ascending order of level number. Finally, surface neighbors of the octants are detected in a specified direction by employing order-mapping asynchronous principle. All neighbors of each octants can be detected in a specified direction during scaninq once.