Beaumont, a former England and British & Irish Lions captain, said he was excited by his new post.
“I’m very honoured to be appointed chairman of the RFU,” he said. “I was fortunate enough to captain my country and everything since then has been about putting something back into a game that is important to so many people.
“We all want to make the game as attractive as possible for all the men, women, boys and girls, who want to play and watch at every level.
“The RFU staff and thousands of volunteers face three years of hard work ahead but the legacy of England hosting Rugby World Cup in 2015 will be enormous and it is our chance to showcase our game throughout the country.”
Lancashire-born Beaumont won 34 caps with England between 1975 and 1982, captaining them to a first Grand Slam in 33 years in 1980.
He has also represented the RFU on the International Rugby Board Council, including a four-year term as vice-chairman, and has been a director of the Six Nations and the Rugby World Cup.
• Scotland will go into the 2013 Rugby Sevens World Cup qualifiers as the seventh seeded European team, after a disappointing finish to the Odense 7s in Denmark yesterday.
The Scots enjoyed a bright start to the tournament on Saturday, topping their group with a clean sweep of day-one wins over hosts Denmark, Germany and series leaders England to make the cup quarter-finals.
However, they could not recapture that form in the day-two knock-out rounds, slipping to three straight defeats to Wales (31-14), Georgia (21-19) and Russia (21-12), to finish eighth in the tournament and seventh overall in the FIRA-AER GP European Sevens Series.
Head coach Graham Shiel said: “We didn’t start well against Wales and struggled for possession, coughed up ball too easily and couldn’t produce a performance to cause teams problems.”