For developing analog circuits at Siemens AG, the method of Harmonic Balance was integrated into the circuit simulator TITAN. The equations of Harmonic Balance are solved by Newton's method. The corresponding Jacobian is a very large sparse block matrix. Hitherto this kind of problem was computed either on a single workstation or on a vector computer. In this paper, we present an algorithm that makes it possible to simulate analog circuits on a cluster of workstations. Since the bulk of data is stored in a distributed way, even very large problems which often cannot be processed on vector computers due to insufficient memory capacity may now be solved.