Keith Wallis, a police officer who lives in Ruislip, is accused of sending an email to South Ruislip MP John Randall falsely claiming he had witnessed the incident in Downing Street.
Mr Mitchell, pictured, was accused of unleashing a foul-mouthed rant at police when they stopped him cycling through the street's main gates.
The Tory MP, who was the government's chief whip at the time, denies claims he called officers "plebs". He admits swearing during the incident but denies he swore at the officers.
In a statement, the office of the DPP, Alison Saunders, said: "We have received evidence in relation to PC Keith Wallis who sent an email to the deputy chief whip, John Randall, who was his MP, saying that he had witnessed the incident.
"We have decided, having carefully considered the evidence in accordance with the Code for Crown Prosecutors, that there is sufficient evidence to charge PC Wallis with misconduct in a public office and that it is in the public interest to do so.
"I should make it clear the misconduct allegation relates to evidence that PC Wallis falsely claimed to have witnessed the incident, not to how the incident was described in his account."
PC Wallis has been charged and is required to attend Westminster Magistrates' Court on December 16.
