In recent years

the deregulation of electric power industry worldwide raises many challenging issues and the competitive electric power markets are becoming more sophisticated. Price forecasting is important of market participants to hedge against volatility of the price and to maximize their benefits and utilities. This paper mainly focus on the prediction of short- term system marginal price. The main influence factors and the variation characteristic of the electric price are deeply discussed after reaffirming the regularity of the electricity price and analyzing the factors affecting electricity prices. Then

it gave brief account of the factor analysis methods which have been used for analyzing in recent years. Finally

it classified and summarized the electricity price forecasting method based on its operating principle. The electricity price forecasting models which was built by the ANN method was also analyzed in it.