In the paper output feedback control of Boolean control networks (BCNs) is investigated. First, necessary and sufficient conditions for the existence of a time-invariant output feedback (TIOF) law, stabilizing the BCN to some equilibrium point, are given, and constructive algorithms to test the existence of such a feedback law are proposed. Two sufficient conditions for the existence of a stabilizing time-varying output feedback (TVOF) are then given. Finally, an example concerning the lac Operon in the bacterium Escherichia Coll is presented, to illustrate the effectiveness of the proposed techniques. (C) 2015 Elsevier Ltd. All rights reserved.