Abstract: This paper introduces a kind design of beam steering calculator chip for X-wave band phased array radar T/R module,It includes multiplication,adder,E^2PROM,serial-parallel conversion,calclulate controller,output controller,etc. ,and has the features of high speed calculate, expandable, miniaturization. In this paper it discussed the need of radar, calculation of project, scheme of realization and key technology,h gives the ensurer of project realization for X-wave band phased array radar T/R module.