Chesterfield inflicted a first defeat in eight games for Blackpool.
Blackpool, without ill striker Keigan Parker, fell behind when Kevan Hurst converted a cross from Caleb Forlan.
It was all over in the 42nd minute when Hurst sent Folan away and the striker went past Michael Jackson and Shaun Barker before scoring from eight yards.
Ian Evatt forced Barry Roche into a diving save in the 79th minute but the centre-half was then booked and will now serve a one-match ban.
Chesterfield: Roche, Picken, Hazell, Downes, Davies, Smith (Hall 76), Niven, Allott, Hurst, Allison, Folan.
Subs Not Used: Jordan, Kovacs, Larkin, Shaw.
Goals: Hurst 13, Folan 42.
Blackpool: Evans, Barker, Jackson, Evatt, Wilkinson (Tierney 74), Jorgensen (Forbes 51), Fox, Southern, Hoolahan, Burgess (Morrell 65), Vernon.
Subs Not Used: Bean, Fernandez.
Booked: Jackson, Evatt.
Ref: R Olivier (W Midlands).