A goal from Darren Hayden 11 minutes from time sealed victory for Wicklow at Pairc Sean Mhic Diarmada, Carrick-on-Shannon.
Three Leitrim points without reply set the pattern of the early exchanges but the dismissal of midfielder Tomas Beirne in the seventh minute was a major blow and Wicklow capitalised.
Leitrim fought back with points from Conor Beirne and Adrian Croal followed by a goal from Beirne to go ahead 1-7 to 0-7 at the break.
Croal extended the lead with a point four minutes into the second half but the home side were reduced to 13 men when defender Barry McWeeney was sent off.
Five Wicklow points put them ahead with 15 minutes remaining and Hayden's goal in the 59th minute followed by two points decided it.
SCORERS -- Wicklow: S Furlong 0-6 (4f), D Hayden 1-1, J McGrath 0-5 (2f), L Glynn 0-2, C McGraynor 0-1. Leitrim: C Beirne 1-2, A Croal 0-4 (1f), D Sweeney 0-2, B McDonald, E Mulligan 0-1 (1f).
WICKLOW -- J Flynn; P Higgins, A Nolan, A Byrne; P Earls, S Kelly, D Hayden; R Finn, N Gaffney; J McGrath, P Dalton, J P Dalton; D Odlum, S Furlong, L Glynn. Subs: C Hyland for A Nolan, J Stafford for JP Dalton, C McGraynor for D Odlum, P McWalter for N Gaffney.
LEITRIM -- C McCrann; G Reynolds, R Gallagher, P Maguire; D Beck, B McWeeney, B Prior; T Beirne, W McKeon; D Sweeney, J Glancy (capt), P Brennan; C Beirne, A Croal, R Cox. Subs: D Reynolds for D Beck, B McDonald for R Cox, J Glancy (St Mary's) for P Brennan, E Mulligan for C Beirne.
REF -- E McHugh (Tyrone).