Max Kretzschmar scored Wycombe's winner for the second successive game as the visitors made it back-to-back victories for the first time since October.
Kretzschmar hit the winner in spectacular fashion when he fired home from 30 yards in the 23rd minute.
Later on, he missed the opportunity to notch his second when he dragged his shot just wide of the post.
Exeter had made the brighter start and Sam Parkin almost broke the deadlock early on but headed over the bar.
The result means that Exeter have won just once in their last 10 matches, while Wycombe are now five points clear of the League Two relegation places.
Wycombe boss Garth Ainsworth told BBC Three Counties Radio:
"The lads are absolutely dead on their feet.
"I couldn't be prouder of the team, everything was fantastic.
"We probably have to get a couple of players in, if I'm being honest, but that's for cover. No-one deserves to lose their place in the team.
"We've got a big run of games coming up - and we believe we can go to Southend on Saturday and win."
Exeter City 30 Pym 02 Butterfield 03 Woodman 29 Grimes 04 Bennett 15 Moore-Taylor 32 Wheeler (O'Flynn - 53' ) 35 Gill 25 Parkin (Nichols - 53' ) 14 Richards (Oakley - 78' ) 07 Sercombe Substitutes 01 Krysiak 05 Baldwin 08 Oakley 11 Davies 19 O'Flynn 20 Nichols 22 Keohane Wycombe Wanderers 01 Ingram 02 McCoy 11 Wood 10 Bloomfield 05 Stewart 06 Johnson 23 Arnold 04 Scowen 27 Styche (Craig - 62' ) 12 Cowan-Hall (Jeffrey - 81' ) 22 Kretzschmar Substitutes 07 Morgan 13 Horlock 15 Jeffrey 18 Kuffour 20 Craig 21 Kewley-Graham
Ref: Michael Bull