Reasonable price signal in electricity market can stimulate resource investment, ensure generation adequacy and it plays an important role in long-term efficient and secure operation of electricity market. The scarcity pricing mechanism based on reserve demand curves is introduced in energy and ancillary services market of the United States. The latest scarcity pricing mechanisms in NewYork, California, Pennsylvania-New Jersey-Maryland and Texas are analyzed and compared, including reserve demand curves, clearing and settlements mechanism. Finally, according to the electricity market reform in China, the corresponding policy suggestions for investment cost recovery mechanism in China are proposed.