In this paper, a new structural matching algorithm for technology mapping is proposed. The algorithm is based on a key observation that the matches for a node in a subject Boolean network are related to the matches for its children. The structural relationships between the library cells are modeled using a lookup table. The proposed method is fast, has low memory usage, and is easy to implement. Experimental results show speedups of 20× over Matsunaga's fast mapping approach, and orders of magnitude over SIS, with the same or slightly better results, and much lower memory utilization.