We present the results of a deep (J=19.1mag) infrared (ZY JHK) survey over the full {alpha} Per open cluster extracted from the Data Release 9 of the United Kingdom Infrared Telescope Infrared Deep Sky Survey Galactic Clusters Survey (UKIDSS). We have selected ~700 cluster member candidates in ~56 square degrees in {alpha} Per by combining photometry in five near-infrared passbands and proper motions derived from the multiple epochs provided by the UKIDSS Galactic Clusters Survey (GCS) Data Release 9 (DR9). We also provide revised membership for all previously published {alpha} Per low-mass stars and brown dwarfs recovered in GCS based on the new photometry and astrometry provided by DR9.