The all-sky survey of the Fermi Large Area Telescope allows a comprehensive search for GeV emission from the supernova remnants (SNRs) in Green's catalog. We have implemented an analysis pipeline based on the Fermi Science Tools to try to identify and characterize the GeV emission toward each remnant in terms of position, extension and spectral properties. Among the 278 sources scanned, more than 50 detections have been obtained, about 30 of which are new SNR candidates and some of which are extended and thus highly likely to be SNRs.