In this paper, the profit’s probability density function of a bidding strategy is developed based on forecasting price with Lognormal distribution, so that the probability of the obtaining specified profit under the scenario can be known, a profit-probability curve can be drawn. The risk curve provides an effective tool for risk analysis. The risk of the bidding strategy obtained by the expected profit maximization is discussed using the profit-probability curve presented in this paper. It shows that risk is implied in this bidding strategy, the risk analysis is necessary.