Winslet - Academy Award-nominated for "The Reader" - lost the best-actress prize to Tilda Swinton, who won for her performance as an alcoholic in "Julia."
"Hunger," director Steve McQueen's harrowing account of the last days of Irish hunger striker Bobby Sands, was named best picture Sunday, beating Boyle's Mumbai rags-to-riches saga "Slumdog Millionaire."
Boyle was nominated for best director, but lost to "The Reader'"s Stephen Daldry.
The best-actor prize was awarded jointly to Michael Sheen, for his performance as talk-show host David Frost in "Frost/Nixon," and Pat Shortt for his turn as a lonely gas-pump attendant in Irish film "Garage."
Martin McDonagh was awarded the best screenplay prize for "In Bruges," and Sally Hawkins won the Peter Sellers Award for Comedy for Mike Leigh's "Happy Go Lucky."
Leigh was given a special award for his contribution to British film and for nurturing new talent.
The Evening Standard awards are sponsored by London's afternoon newspaper and selected by a jury of film critics.