The recent decades have witnessed the development of a new generation of space structures called free-form space structures. In this new family of space structures, due to the geometric nature of the structure, the orientation of the members varies substantially within the joints, meaning that the members need to be connected to the joints at different angles. The wide distribution of these angles throughout the structure will significantly affect the cost of fabrication. Therefore, accurate and automatic calculation of connection angles and their optimizations have always been of interest to researchers and manufacturers. This article has the following two main objectives. The first objective is to provide geometric calculations and obtain the connection angles of single-layer lattice space structures. The second, and more important objective is to review the existing methods and to develop a geometrical method for their optimization, referred to as the “node orientation optimization” method throughout this article. Using the mentioned method, a series of optimizations are carried out in a number of free-form lattice space structures and the results are studied.