The Reds eased past North Somercotes United Reserves 3-0 in the final, Sam Eggleston coming off the bench to score twice, adding to Bailey Wright’s strike.
Louth OB’s first team won the Town Trophy earlier this month.
The Reds and Somercotes met three days later and played out a 2-2 draw in the group stages of the Tim Sales Trophy on Saturday.
The point confirmed top spot in the group for the Louth side ahead of the knockout stages.
In the other Group A game, Alford Town Reserves went down 1-0 to Marsh Rovers to finish bottom.
And in Group B, bottom side Louth Old Boys Vets went down 5-0 at Burgh Athletic.
Elsewhere, Alford Town have their work cut out to reach the Cusworth Cup final after losing the first leg of their semi-final 3-0 at home to Tetney Rovers.