Abstract: Y(NO₃)₃ or Ce(NO₃)₃ was doped into novolac-type phenolic resin with a solution mixing method, and phenolic resinbased activated carbons rich in mesopores were obtained by steam activation. The as-prepared samples were characterized by infrared spectroscopy, thermogravimetry, nitrogen adsorption and scanning electron microscopy. Results indicate that the doping of Y(NO₃)₃ or Ce(NO₃)₃ into phenolic resin is favorable for the activation of phenolic resin-based carbon in steam, improving the activation rate and promoting the formation of pores. The efficiency for carbon gasification increases with increasing catalyst content and reaches a maximum at 4% by weight for both catalysts. The maximum is thought to be due to the agglomeration of metal particles and a decreasing of contact surface area between carbon and metal particles at the high metal content. Y(NO₃)₃ can accelerate the formation of micropores and mesopores simultaneously with the former more developed. However, Ce(NO₃)₃ shows an obvious effect on the development of mesopores.