Danny Slatter fired Gravesend's winner as the visitors kept themselves in the play-off hunt with a comeback victory. Charlie MacDonald and Omome Sodje went close for the visitors, but Northwich took the lead when Carlos Roca netted Felix Bastians' cross after 10 minutes.
Gravesend fought back well to level as Sodje headed home in style.
And while Slatter's strike on the cusp of half-time proved to be the winner, the hosts almost salvaged a point when Stephen Payne's shot was tipped over.
606 DEBATE: Give your thoughts on the match
Northwich: Senior, McCarthy (Sale 78), Griffiths (Payne 54), Charnock, Young, Roca (Byrne 73), Carr, Elliott, Bastians, Brayson, Dodds.
Subs Not Used: Connett, Battersby.
Goals: Roca 11.
Gravesend: Cronin, McCarthy, Ross Smith, Hawkins, Keeling (DeBolla 66), Slatter, Quinn, Long, Sodje, MacDonald, Opinel.
Subs Not Used: Mott, Purcell, Ekoku, Coleman.
Booked: Hawkins, Quinn, McCarthy, Opinel.
Goals: Sodje 43, Slatter 45.
Att: 813.
Ref: J Waugh (Sheffield).