Lettering robot manipulator is a kind of teaching and science popularization device which is fit for schools and science museums and so on. The basic construction, parameter and control system are introduced. The homogeneous transformation equation of manipulator is created according to the Denavit-Hartenberg method, and the kinematics solution and inverse kinematics solution are analyzed. The present state of vector font handling in CAD/CAM application is summarized. Because it is difficult to analyze directly the format of TTF font file and to get the outline of a certain letter, we call the windows API function GetGlyphOutline to read the data of TTF vector font in windows system. On the dot array mongline font we have vectorize it with VC++.Through the wectorised data and kinematics equation,the track programming and control and so on can be realized.