Conservative Central Office said the shortlist comprised: Lord Archer of Weston-super-Mare; Robert Blackman; Andrew Boff; Bernard Gentry; Patrick Ground QC; Mark Kotecha; Steven Norris; and John Wilkinson MP.
Michael Ancram, the party's chairman, said London Conservatives had "an excellent choice" of candidates.
All eight will be interviewed on 6 September by an electoral college comprising the party's mayoral selection executive and a representative from each of the 74 London constituencies associations. The shortlist will then be whittled down to three or four candidates.
A hustings meeting at which every member of the London party can vote will be held on 14 September.
The top two candidates from that meeting will then be entered into a postal ballot of all the party members in the capital.
The count and the announcement of the result will take place on 1 October.
Mr Ancram said the candidates were participating in "the most open and democratic" selection process for candidates for mayor of London of any political party.
He said: "Our members will now decide who the party's candidate will be to stand for the position of Mayor of London. Having made its democratic choice the whole party will unite behind that candidate to ensure their election as mayor of London on 4 May, 2000."