Truss, 46, announced her candidacy in the Daily Telegraph newspaper on Sunday evening, saying she had "a clear vision of where we need to be, and the experience and resolve to get us there".
The bid by Truss, seen as a frontrunner in the Tory leadership contest, followed that of former defence minister Penny Mordaunt as the race expanded to 11 candidates.
Many of the 11 leadership hopefuls looking to become the Tory party leader have set out competing for tax plans as a core element of their proposals, BBC reported.
The 1922 Committee of backbench Tory MPs that organises contests will meet on Monday to decide the timetable and rules of the leadership race.
The two-stage process will see Conservative MPs whittle down the candidates to two, through voting rounds, before Tory party members decide the winner.
Truss indicated that she would echo her rivals in planning to slash corporation tax, reverse the National Insurance hike and reform business rates.
The foreign secretary said she would "fight the election as a Conservative and govern as a Conservative".
The newly-appointed Foreign Office Minister Rehman Chishti also declared his candidacy on Sunday, with the 43-year-old speaking about the importance of lower taxes, a small state and a big society.
ZZ/PR