Jeffrey Schlupp, Andros Townsend and Luka Milivojevic were the goal scorers for Crystal Palace.
Pep Guardiola's side took the lead when Kevin De Bruyne marked his return from injury with a fine finish in the first half at the King Power Stadium.
Vichai Srivaddhanaprabha was among five people killed when his helicopter crashed outside the King Power Stadium on October 27.
The charismatic Thai had become a beloved figure in the club and the city.
Kasper Schmeichel said Vichai Srivaddhanaprabha transcended the traditional image of a Premier League club owner.
Vichai Srivaddhanaprabha died last week, along with four others, when his helicopter crashed after taking off from Leicester's pitch following a match.
Leicester City's Midfielder Demarai Gray was booked by the referee in the 55th minute of Premier League game against Cardiff City
Leicester's players huddled together in celebration at full-time, with many of them due to fly to Thailand to join Vichai's funeral.
Kasper Schmeichel has made 303 appearances for Leicester since being signed by Vichai Srivaddhanaprabha in 2011.
Leicester City's Premier League match away to Cardiff on Saturday will go ahead as planned.
Vichai Srivaddhanaprabha's son Aiyawatt thanked people for the messages of support from across the world.
Vichai Srivaddhanaprabha, 60, died when his helicopter plummeted into a car park outside the King Power stadium.
Vichai Srivaddhanaprabha's son and widow were seen laying a wreath among a sea of tributes from fans outside the stadium.
Vichai Srivaddhanaprabha, who died following a helicopter crash on Saturday, was also the owner of a Belgian football club, Oud-Heverlee Leuven.
Vichai Srivaddhanaprabha was flying out of the club's stadium when his helicopter crashed in a parking lot.
Srivaddhanaprabha was reportedly on the helicopter that crashed on Saturday. An official confirmation on his death is yet to come from Leicester City.
Dozens of candles and flowers could also be seen among the tributes, as well as an image of Ganesh -- a Hindu god often found at Thai Buddhist temples.
The helicopter, belonging to Leicester City owner Vichai Srivaddhanaprabha, was seen enveloped in flames in mobile phone images from the scene.