First-half efforts from Josh Magennis and Jason Kerr gave the Latics a half-time lead before Dylan Connolly pulled one back early in the second period.
Any hopes of a comeback were dashed, however, when Stephen Humphrys and Will Keane added two further goals.
The result left Derek Adams still searching for his first win since returning to the club and the Shrimps struggling to escape the bottom four.
The home side started the game with a flurry as James McClean volleyed over, Keane headed straight at Trevor Carson and Tom Naylor drilled a shot off target.
That pressure paid off on 18 minutes when Tendayi Darikwa crossed from the right and Magennis flicked a header past Carson.
The Shrimps then began to cause some problems of their own with Cole Stockton’s volley deflected just over and Aaron Wildig’s volley forcing a point-blank save from Ben Amos.
Wigan defender Jack Whatmough almost put through his own goal as he sliced a Ryan Cooney cross inches wide.
Then, for the third game in succession, the Shrimps conceded just before half-time as a corner was flicked on and Kerr headed home from close range.
Morecambe did score the goal their efforts deserved with a penalty three minutes after the break.
A Stockton shot hit the arm of a Wigan defender and Connolly beat Amos from 12 yards to score his first goal for the club.
The goal gave the Shrimps a lift but the home side showed their class as they raised their game.
Humphrys forced Carson into a superb save and Jacob Bedeau produced a vital block before Wigan made it 3-1 on 66 minutes.
Carson punched away Darikwa’s cross but it fell perfectly for Keane to send a looping header over the keeper.
Two minutes later, the Latics completed the scoring when Humphrys volleyed into the bottom corner.
Wigan Athletic: Amos, Kerr, Whatmough, Tilt, Darikwa, Power (Shinnie 78), Naylor, Power, Keane, Magennis, Humphrys (Edwards 88). Subs not used: Jones, Watts, Pearce, Massey, Bennett.
Morecambe: Carson, Cooney, O’Connor, Bedeau (Gibson 88), Leigh, Diagouraga, Wildig, McLoughlin (Phillips 74), Gnahoua (Ayunga 88), Stockton, Connolly. Subs not used: Smith, Obika, Mensah, Fane.
Referee: James Oldham.