To improve indoor coverage and network capacity, the use of hierarchical macro/femto cell networks is regarded as the most promising approach. We present an efficient handoff algorithm to support the inbound mobility from macro cells to femto cells under the consideration of large asymmetry in the transmit power of the cells. Numerical analysis reveals that the proposed algorithm yields a higher probability that the user will be correctly assigned to the femto cell while maintaining the number of handoffs at the same level.