Vichai, 60, and four other people died in a horrific helicopter accident moments after they departed the club's pitch a week ago, bringing an abrupt end to the fairytale life of Thailand's fifth-richest man.
He rose from having a single store in Bangkok to owning the duty-free King Power empire, whose shops are ubiquitous in Thailand's tourist-heavy airports.
Using the profits from his monopoly Vichai snagged Leicester City and helped turn it from an unremarkable English club to a shock winner of the Premier League title in 2016.
Thais were stunned by the tragic demise of a man known mainly for one business success after another but who owed much of his ascent to canny navigation of Thailand's unpredictable politics and elite society.
That included the monarchy, links reflected in the name of his company and the former king's act of royally bestowing on Vichai a surname that translates to "auspicious and prosperous light".
Vichai's body was flown back to Thailand and taken to Wat Thepsirin on Friday where prominent individuals close to the family wore black for a private gathering ahead of the official ceremony which starts Saturday evening and lasts until November 9.
'Honour his name'
The ceremony will have regal touches, with an octagonal urn among the items given by the monarchy and court musicians playing drums and flutes during royally-sponsored bathing rites.
Buddhist monks will recite prayers from religious texts and afterwards the body will be kept for 100 days before a cremation but a date has not been set.
Members of the Leicester team including coach Claude Puel are due to fly to Thailand to pay their respects after an afternoon away match against Cardiff City Saturday.
"We all spoke about ... wanting to play, it's what Vichai would've wanted and that's what we are going to do," striker Jamie Vardy told Sky Sports, adding that they would "honour his name" with their performance.
Vardy, goalkeeper Kasper Schmeichel and captain Wes Morgan, are expected to travel along with Puel and senior staff.
Vichai leaves behind a wife and four children, two sons and two daughters.
All five are on the executive board of King Power, which faces an uncertain future.
In the first public reaction from the family, Vichai's youngest son Aiyawatt -- better known by his nickname "Top" -- said in an Instagram post this week that his father had "left me with a legacy to continue and I will do everything I can to carry on his big vision and dreams."
The four other crash victims were identified by British police as Nursara Suknamai -- an actress and a runner-up in Miss Thailand Universe in 2005 -- and Kaveporn Punpare, both members of Vichai's staff, pilot Eric Swaffer and passenger Izabela Roza Lechowicz.