The 26-year-old from Yorkshire mustered a gutsy finish to triumph in the 130km event to claim the coveted white jersey with rainbow stripes in Virginia, United States.
Armitstead had to settle for a silver medal in the road race at the London 2012 Olympics and has now trained her sights on improving on that performance at next year’s Games in Rio de Janeiro.
“That would surpass this if I could achieve that. That will be my focus now for the next 12 months. All in for Rio,” she said.
“I can’t get my head around it yet, really. I’m just so focused on the process all the time.
“Crossing the line and being world champion, I’ve always dreamt about it and now I’ve done it. It’s quite a surreal feeling, but obviously very special. Very happy.”
Armitstead’s victory represented a second medal of the championships, having helped her professional team Boels-Dolmans win silver in the time trial last week. She is the fourth British woman to win the road cycling world title, after Nicole Cooke in 2008, Mandy Jones in 1982 and two-time champion Beryl Burton, who won in 1960 and 1967.
Slovakian Peter Sagan was crowned the men’s champion last night after he successfully surged clear with a little under 3km remaining. Sagan, 25, won by three seconds from Australian Michael Matthews and Ramunas Navardauskas of Lithuania, with Ben Swift the best-placed British rider in 22nd.