Tories in the marginal West Yorkshire seat of Calder Valley have selected a new parliamentary candidate after sacking their previous choice.
Mrs Truss is preparing to relocate to West Yorkshire from London
Elizabeth Truss, head of public affairs at telecom giant Cable & Wireless in London, was voted in on Saturday.
The 29-year-old replaces Sue Catling, who was deselected last month after claims of misconduct, which she denies.
Mrs Catling halved Labour's majority at the 2001 election, losing the seat by 3,000 votes to Christine McCafferty.
Mrs Catling had survived two previous attempts by the party to deselect her over unspecified allegations, but was voted out at the third attempt.
The former Cheshire Businesswoman of the Year accused the party of "orchestrating the most sustained campaign of dirty tricks any candidate has had to put up with anywhere in the country".
In Saturday's final run-off at Ripponden Conservative Club, Mrs Truss, who is originally from Leeds, defeated rival Sharon Buckle, who stood for the East Midlands at the European elections in 1999.
The victory means a return to West Yorkshire politics for Mrs Truss, who gained an 8,000-vote swing in the Hemsworth constituency in 2001.
No-one from the Ripponden Conservative Club was available for comment.