Anastasia Dobromyslova beat Lisa Ashton 2-1 at Lakeside to claim her third BDO Women's World Championship.
The Russian, who is now based in Cheshire, took a vital break in the third leg of the deciding set to add to the titles she won in 2008 and 2012.
England's Ashton had earlier fought back from a set down with the help of an excellent 120 checkout.
Second seed Dobromyslova is back with the BDO after spending three years with the rival PDC governing body.
"I still don't realise I have done it," she said. "It was such a tough game. If it had gone to 2-2 in the final set it could have been anyone's title."
Ashton, beaten in her first Frimley Green final, said: "I am gutted at losing but was really pleased to get through to the final."