The winger, who turns 23 on Sunday, is yet to make his debut for the Exiles after joining from Yeovil last summer.
Ralph began his professional career at Peterborough after spending time in the youth set-ups at Tottenham Hotspur and Ipswich Town.
He scored two goals in 41 appearances for Yeovil during a three-year spell with the Glovers.
National League side Aldershot Town have signed Newport's Nathan Ralph on loan until the end of the season.