Adam Cunningham's first goal of the season got Bromley off to the perfect start when he converted Joe Anderson's left-wing cross.
The visitors doubled their advantage when Jordan Higgs got on the end of a corner at the far post and headed home to earn a deserved 2-0 lead at the break.
Jordan Lussey pulled a goal back for Southport with a wonderful strike into the top corner but the Ravens held off a late fightback from the hosts to grab all three points and move up to 18th in the table.
Report supplied by the Press Association.
Match ends, Southport 1, Bromley 2.
Second Half ends, Southport 1, Bromley 2.
Substitution, Southport. Bobby James Moseley replaces Liam Nolan.
Alan Julian (Bromley) is shown the yellow card.
Blair Turgott (Bromley) is shown the yellow card.
Substitution, Bromley. Bradley Goldberg replaces Dave Martin.
Dave Martin (Bromley) is shown the yellow card.
Jordan Lussey (Southport) is shown the yellow card.
Substitution, Bromley. Daniel Ajakaiye replaces Adam Cunnington.
Substitution, Southport. John Cofie replaces James Caton.
Substitution, Bromley. Lee Minshull replaces Tobi Sho-Silva.
Goal!  Southport 1, Bromley 2. Jordan Lussey (Southport).
Liam Nolan (Southport) is shown the yellow card.
Substitution, Southport. Gary Jones replaces James Gray.
Second Half begins Southport 0, Bromley 2.
First Half ends, Southport 0, Bromley 2.
Goal!  Southport 0, Bromley 2. Jordan Higgs (Bromley).
Goal!  Southport 0, Bromley 1. Adam Cunnington (Bromley).
First Half begins.
Lineups are announced and players are warming up.
Bromley recorded a much needed win over Southport to secure their first National League victory in three matches.