British & Irish Lions fly-half Charlie Hodgson produced a flawless kicking performance with six from six giving him a 17-point haul, while Lions winger Jason Robinson scored the only try of the game - a sublime 50-metre effort in the 31st minute.
The champions for the last three seasons looked bereft of ideas and energy after last week's titanic struggle with Gloucester, and they had no answer to Hodgson's superb management of the game and a dogged performance from a Sale pack in which Lion Jason White and Sebastien Chabal were outstanding.
Wasps, who suffered their first ever play-off defeat, scored 12 points from the boot of Mark van Gisbergen, but they lacked a cutting edge in the backs and were unable to break down a resolute Sale defence.
The game marked the end of an illustrious career for Wasps, England and Lions scrum-half Matt Dawson, who came on as a second-half substitute, while Stuart Abbott will move to Harlequins next season.
The defeat draws a close on a difficult first season in charge for Wasps director of rugby and British & Irish Lions coach Ian McGeechan, while Sale march into the May 27 final to face Leicester full of confidence after a this resounding win in front of a packed house at Edgeley Park.
Leicester cruised into the Guinness Premiership final by demolishing form team London Irish at Welford Road.
The Tigers, who were last crowned English champions four years ago, left Irish reeling by building a 15-point interval advantage through tries from wing Alesana Tuilagi and scrum-half Harry Ellis.
And there was no way back for the Exiles, whose hopes of Premiership glory were dashed by a first away league defeat since Leicester crushed them 35-3 in November.
Brian Smith's men could not scale the heights attained in a show-stopping display against deposed champions Wasps two weeks ago, and if anything, the whole occasion seemed a game too far.
Second-half touchdowns by substitute wing Leon Lloyd, who claimed a quickfire double, and British & Irish Lion Geordan Murphy finished off a lacklustre Irish outfit, while fly-half Andy Goode booted three penalties and three conversions.