In this paper, a new bidding strategy for pay-as-bid market suppliers is introduced. This method is based on a systematic analysis of interactions of market with the suppliers via several market indices as well as forecasting important indices by artificial neural networks. Besides, the proposed method considers the practical limitations in the system and deals with incomplete information handling, closely. Next, a strategic bidding approach is proposed for optimal bidding by the suppliers. In these investigations, the paper focus is on the experimental situation of Iran electricity market as a pay-as-bid market and a sample generating company with several generating units from this market is considered as the benchmark. The results of applying this approach to this generating company are representative of good performance of the proposed method. (C) 2010 Elsevier Ltd. All rights reserved.