We studied microhabitat use by Proechimys semispinosus (Central American spiny rat) by livetrapping along transects in 5 forested sites in central Panama. Microhabitat was quantified by measuring 14 variables at each sampling station. Relative abundance of P. semispinosus was 1.86 individuals/100 station-nights, which was typical of abundances of this species and other members of the genus. Spiny rats were distributed throughout sampled microhabitat space defined by factor analysis of 14 variables. We used logistic regression analysis to relate presence–absence at trap stations to microhabitat structure. Variables describing disturbed and younger forest were strong predictors of presence at trap stations. Associations of P. semispinosus with younger forest (smaller trees and lianas and lower canopies) and treefall gaps within older forest may have implications for regeneration of local forest patches through the activities of these rodents as seed predators and dispersers of seeds and arbuscular mycorrhizal fungi spores.