In this paper, the hydrogen storage in pretreated carbon nanotubes is studied. The results indicate that there exists an uptake maximum at certain pressure between 0~12MPa, and this maximum is related with the kind and the treatment of the samples. For different quantity and different kinds of alkali-doped samples, the alkalis plays different roles. High-temperature activation is effective for adsorption. At room temperature, under 9MPa, the highest uptake is about 4.48%(mass ratio). Increasing ambient temperature properly benifits adsorption．