The present invention provides an electret fiber sheet having superior recovery of airflow volume by heat treatment and having high air permeability. The electret fiber sheet of the present invention is a nonwoven fabric formed from long fibers that are formed from a thermoplastic resin and have an average single fiber diameter of 0.1 to 8.0 μm, wherein a bulk density of the nonwoven fabric is 0.05 to 0.30 g/cm3 and the long fibers contain a crystal nucleating agent at 0.005 to 1.0% by mass.