Abstract: To reduce the effects of multi-path and highly reflective scatterers in a clutter environment, a microwave imaging algorithm for a perfectly electrical conducting target was proposed based on the adaptive focusing characteristic of time reversal (TR). In this algorithm, the contour of an unknown target is approximated by a trigonometric series. The scattering problem is simulated using the finite-difference time-domain (FDTD) technique, and the inverse problem is translated into a restrained optimization problem and the coefficients of the trigonometric series are optimized by the genetic algorithm (GA). With this algorithm, the image reconstruction of a two-dimensional perfectly electrical conducting target in a cluttered environment with many random scatterers can be done by only a single antenna. To demonstrate the validation of the proposed algorithm, the simulation of two numerical examples was carried out.