This study addresses the characteristics of polycrystalline-silicon thin-film transistors (poly-Si TFTs) with 3-D finlike channels fabricated using ultraviolet nanoimprint lithography. The poly-Si 3-D finlike channels with a line width/space ratio of about $sim$1 : 1 were fabricated and studied by scanning electron microscope and transmission electron microscopy. The poly-Si TFTs with 3-D finlike channels, fabricated using the nanoimprint technique, have superior performances in comparison to that with the single channel. Besides, the characteristics of poly-Si TFTs, such as the transfer characteristics, output drain current, transconductance, on/off current ratio, subthreshold swing, and field-effective mobility, with respect to the width/space/height of 3-D finlike structures were also investigated. The proposed approach can be utilized to fabricated high-performance poly-Si TFTs or high-sensitivity biosensors at low cost.