The undercover reporter known as the "Fake Sheikh" has denied conspiring to pervert the course of justice over the case of pop star Tulisa Contostavlos.
Mazher Mahmood, 52, is alleged to have misled the court during the collapsed drugs trial of the former N-Dubz star and X Factor judge.
The Sun journalist, of Purley, south London, is accused with Alan Smith, 66, a retired driver from Dereham, Norfolk.
The charge states that between 22 June 2014 and 22 July 2014, Mahmood and Smith conspired together to do an act, namely that Smith would change a draft statement to police, with the intention to pervert the course of justice.
The defendants appeared for a plea and case management hearing at the Old Bailey before the Recorder of London, Nicholas Hilliard QC.
Mahmood wore a pinstriped suit with blue shirt and tie under a hooded jacket and sat side by side in the dock with Smith, who wore a dark suit and red tie.
They pleaded not guilty to the charge before the judge set a trial date of 19 September, with a pre-trial review at the Old Bailey on 10 June. Both men are on unconditional bail.