The deserved victory at the King Power Stadium also moved the Foxes above promotion rivals Blackpool in the Championship table.
Andy King opened the scoring in the 35th minute, the midfielder prodding a low shot under Matt Gilks after Dyer had supplied a neat through-ball.
Dyer then had a hand in the second late on, breaking clear and slipping the ball around the onrushing Gilks to provide substitute Neil Danns with a simple chance that he gleefully converted.
Blackpool may have considered themselves somewhat unfortunate to be behind at the break, but they barely threatened in the second half and could have few complaints at the final score.
Leicester, who improved as the match went on and could have scored more were it not for the impressive efforts of Gilks, have now won two and drawn one in Pearson's second spell at the helm to climb into the top six.
The Seasiders are two points behind them in eighth, having failed to fire on Ian Holloway's return to his former club.
Sol Bamba replaced Sean St Ledger at the heart of Leicester's defence in the only change to either starting XI, while Kevin Phillips returned to Blackpool's squad and was named among the substitutes.
After a minute's applause in honour of the late Gary Speed, both sides struggled to carve out chances in the early stages, although Lomana LuaLua represented a lively presence in attack for the visitors.
Both goalkeepers remained untroubled until the 27th minute, when, from a Leicester corner, Gilks had to react well to tip Lee Peltier's header around his right-hand post.
Blackpool responded immediately and Kasper Schmeichel was forced to parry away a header from Gary Taylor-Fletcher after the striker had been picked out by Neal Eardley's cross.
It wasn't long before the Foxes were back on the attack, however, and Jermaine Beckford drew a fine save from Gilks with an acrobatic half-volley from eight yards.
Moments after Chris Basham had come on for Blackpool in place of the injured Alex Baptiste, Leicester then took the lead through King's fourth goal of the season.
The tricky LuaLua curled an effort wide from the edge of the area as the Seasiders tried in vain to hit back before the interval.
Yet it was all Leicester at the start of the second half and skipper Matt Mills twice went close with headers from Paul Gallagher free-kicks either side of Beckford drawing another stop from Gilks.
Blackpool's keeper denied Beckford for a third time in the 59th minute after the former Leeds and Everton forward had struck a powerful left-footed shot on the turn.
Beckford was then replaced by Steve Howard, who curled a 20-yard shot narrowly over following good work from fellow substitute Danns.
Gilks was called upon once again in the 74th minute when Dyer cut in from the left and fired towards goal, while David Nugent also drilled an effort inches wide.
Yet a second goal soon arrived and Nugent could even have added a third late on, only to miss the target when one on one with Gilks.