Although the Blues didn't reach the level of performance in the first half that they have in recent weeks, they battled back for the three points thanks to Dillon North's double.
Manager Daren Pearce said: "After conceding early in the first half, we got back on level terns before half-time. Second half we came out a lot better and were assured.
"We scored a really well worked second goal and could have added to this but a good goalkeeping performance from the visiting keeper kept the score at 2-1 on full time."
Selsey are at home to Billingshurst on Tuesday night and go to Oakwood on Saturday.