For the second league in succession the Shrimps took the points thanks to a goal from an opponents' defender just before the break.
An Adriano Rigoglioso corner was only parried downwards by Lance Cronin and as the ball bounced in the goalmouth, Ross Smith headed into the top right hand corner of his own goal.
It was a goal that in the end proved vital as the win saw the Shrimps maintain their steady climb up the table and move level with Gravesend on points.
The goal itself came as something of a shock as it was the visitors who had done most of the early pressing without ever really threatening.
Morecambe keeper Steven Drench was forced into a neat save from Charlie McDonald on 15 minutes and Onome Sodje came close to connecting with Sacha Opinel's early cross as he came rushing in at the far post. Opinel volleyed wide of the target from 25 yards on 22 minutes as Gravesend found it difficult to break down a Morecambe defence superbly marshalled by the returning Jim Bentley and the ever consistent Chris Blackburn.
It took the Shrimps almost half an hour before they threatened the Gravesend goal when Garry Thompson, back in the side after serving a three match ban, headed a deep Michael Howard cross inches wide of the left hand post before that vital opening goal.
The second half saw Morecambe produce the better moments with Wayne Curtis a leading figure.
Curtis, another returning to the squad after injury, was moved up front for the second period and his strength caused problems.
Helped on more than one occasion by a generous linesman, he broke free of the defence on 59 minutes and produced a shot that was well saved by Cronin.
From the resulting Michael Twiss corner Opinel came close to adding a second own goal with a miscued clearance that flew just over the top of his own goal before Curtis threatened again with a fierce drive that whistled just wide of the left hand post.
After struggling to make any progress in the second period Gravesend raised their game noticeably when Jon Keeling came of the bench with 15 minutes to go.
He immediately began to cause Morecambe problems and on 77 minutes MacDonald came close again with a shot on the turn that was well gathered by Drench.
As Gravesend pressed gaps opened up at the back and Garry Thompson should have done better than see his square ball for Curtis cut out by Ross Smith when the Shrimps had a man over.
The home side were then denied a clear penalty when trialist Conal Platt was brought down in injury time after a storming run into the box but it mattered little as the whistle blew moments later to signal another win for Sammy McIlroy's improving side.