Returning farmland to forest (RFTF) project is one of the most critical ecological restoration projects in Bashang area, and its ecological service value has been paid more and more attention. Although the herb layer of the artificial forest was a vital indicator to biodiversity conservation and ecosystem services, the relevant researches were much less than expected in this area. We surveyed herb diversities of these forests that were planted in four different periods from 1970s to 2000s of the returning farmland to forest project. Then, the herb diversity of returning farmland to forest habitat was compared with that in abandoned farmland and the natural forests. The effect of the soil character, tree and shrub layer on herb diversity was also analyzed. The results showed that there was no significant difference of herb diversity among different periods of RFTF projects. While all of them were significantly lower than that in the abandoned farmland and the natural forests species richness of herb layers was significantly and positively responded to the content of soil alkali-hydrolyzable nitrogen species richness and densities of shrub. The Simpson diversity of herb layer was negatively responded to the densities of tree. The research revealed that the herb diversities of RFTF habitats might be lower than that we expected, improving vertical spatial structures and construction mode might be helpful to increase the herb diversity level. In order to preferably realize ecological benefits of future ecological restoration projects in Bashang area, it needs to weigh the different relationships of ecological ecosystem service functions, choose ecological restoration methods based on local conditions, and emphasize the importance to natural restoration and diverse restoration methods.