Ipswich had the better of the first period, but couldn't break down a Blackpool defence which lost both starting centre-halves Michael Jackson and Ian Evatt in the opening 31 minutes.
Early on, Paul Rachubka made a fine diving save to tip away a low Walters drive, and the same player then scuffed a good chance from an Alan Lee cross, allowing sub Danny Coid to clear off the line.
The hosts were denied again a minute later, when Tommy Miller's corner was met by a firm Jason De Vos header, but Claus Jorgensen headed off the line.
Ipswich went ahead on 50 minutes when Lee laid off a Danny Haynes cross for Macedonian international Sumulikoski to crash a 20-yarder in off the post.
Miller was denied by Rachubka before Town went two up when Lee lifted the ball forward and Walters held off makeshift centre-half Keith Southern to sidefoot home his 12th goal of the season.
Rachubka denied sub Alan Quinn and Walters as Ipswich threatened to run riot, before Dickov made it interesting with an 89th minute goal.
He took advantage when a midfield challenge broke towards his own goal off Quinn, allowing the on-loan Manchester City striker to run on and score, even though he was standing in an offside position.
However, Ipswich played out the final moments with no further alarms to record a deserved victory.