AbstractVariation in diversity of communities of small mammals in seven different habitats from the median subtropical evergreen broad leaved forest belt in the Dujiangyan Region was studied from the end of October to the beginning of November 2000. Twelve species, comprising ten Muridae (Rodentia) and two Soricidae (Insectivora), were captured. The total rate of small mammals captured was 10.7%.Analyses of diversity of small mammals in different habitats show that species diversity index (1.84) and evenness index (0.95) are highest in secondary forest, where human disturbance has been moderate in recent years. Those in shrubland, secondary forest/primary forest and abandoned farmland are also high, while species are rare and the species dominance index is high (0.57) in farmland, where human disturbance is most serious. Species diversity index (1.34) and evenness index (0.83) are also lower in plantation of Cryptomeria fortunei. Species diversity index in primary forest (1.43) is slightly lower than that in secondary forests (1.85 and 1.46), shrubland (1.64) or abandoned farmland (1.66), which results from habitat degradation. Based on similarity indices, seven habitats can be clustered at the level of 0.095 with systematic clustering. Small mammals of forest type are mainly distributed in shrubland, secondary forests and primary forest, which are clustered into one group. Farmland and plantation of C. fortunei are dominated by Rattus nitidus and belong to the farmland type. Abandoned farmland is an ecotone of farmland and forest, because of its higher diversity index (1.66) and higher rate of small mammals of farmland type (46.7%). The results show that diversity is the lowest in habitats where disturbances are most serious (e.g. farmland and plantation of C. fortunei) and highest in moderately disturbed habitats (e.g. secondary forest, shrub and abandoned farmlands) and slightly lower in disturbed habitats (e.g. primary forest).