Kevin Ellison's brace led Morecambe to their first win of the season as they ended Exeter's unbeaten league run.
Morecambe's Jack Sampson had a header cleared off the line, but the unmarked Ellison nodded home just after the break to put his side in front.
Sampson and Ellison combined for the second as the striker lobbed keeper Artur Krysiak from 12 yards out.
Aaron Davies and John O'Flynn both went close for the visitors, but home keeper Barry Roche kept them at bay.
VIEW FROM THE DRESSING ROOM
Exeter manager Paul Tisdale told BBC Radio Devon:
"It was a very competent first half and a poor second half.
"We had three or four really good chances in the first half, but I'm not going to show any frustration to the players - they want to score, but some days they don't go in.
"My main instructions [at half-time] were to be as good as we could in the first five minutes and make sure we got back in control like we were in the first half, but we didn't do that, did we?
"I was disappointed with the first goal. He had a free header from eight or nine yards out, which is very disappointing from a defensive point of view."
Morecambe 01 Roche 05 Hughes 06 Diagne 15 McCready 22 Parrish 04 Kenyon 10 Williams (Drummond - 82' ) 17 Fleming 09 Sampson (Amond - 82' ) 11 Ellison 14 Marshall (Mwasile - 73' ) Substitutes 25 Arestidou 03 Threlfall 23 Doyle 16 Drummond 19 McGee 20 Mwasile 27 Amond Exeter 01 Krysiak 03 Woodman 04 Bennett 06 Coles 16 Dawson 08 Oakley 11 Davies 14 Doherty (Keohane - 64' ) 32 Wheeler (Reid - 83' ) 19 O'Flynn 25 Parkin (Gow - 64' ) Substitutes 30 Pyn 15 Moore-Taylor 22 Keohane 29 Grimes 10 Gow 18 Reid 20 Nicholls