During the process of "Digitizing" which requires execute of huge amount of sequential vertices and segments for creating layers that are in vector base, cartographers face two main problems which are; the quality of presented data and the file size. Despite that the process of line generalization is a superior solution to overcome these two problems, it produces errors such as spike, line-crossing, line-coincident, and polygon knot in the topological structures of lines being generalized. Geometric data that have complex topological structure can be simplified and smoothed by applying four types of techniques based algorithms, which are; Nth Point, Jenks, Point Remove, and Bend Simplify. In this paper, through an experimental comparison study, it is proved that the bend simplify algorithm is the best approach amongst four types of algorithms applied to line generalization that preserves the quality of the line being generalized and reduce the file size moderately.