Scott had been charged under RFU Rule 5.12 with "conduct prejudicial to the interests of the Union or the Game" for providing false and misleading information to the governing body over the registration of Exiles scrum-half Tyson Keats.
Keats appeared in 10 Premiership games this term while not holding effective registration with the RFU. London Welsh have been handed a five-point deduction from their Aviva Premiership tally and a £15,000 fine as a result, although the club have confirmed they will appeal the decision.
An RFU statement read: "Mike Scott was today suspended from the management, coaching or playing of rugby union and membership of any club for life following an RFU Misconduct Hearing.
"The former London Welsh team manager may not apply for the order to be lifted for 10 years."