— This paper presents GAPSYS - a genetic algorithm based automated circuit synthesis tool for passive analog circuits. It describes the procedure for developing both the circuit topology and the component values for a passive analog circuit comprising of R, L and C components from a given set of specifications. The novelty of the work pertains to the component value assignment procedure for the initial set of circuits and the crossover techniques employed. Experiments conducted on two low-pass filter design benchmarks demonstrate the effectiveness of GAPSYS as a synthesis tool.