Drogba won three Premier League titles, four FA Cups, two League Cups and, most memorably, the 2012 Champions League when his penalty in the shootout clinched victory for the Londoners against Bayern Munich in the final at the Allianz Arena.
He scored 157 goals in 341 appearances for Chelsea between 2004-12 and was voted the greatest player in the club's history.
"It is the club where I experienced everything," Drogba told the UEFA website (www.uefa.com). "I experienced the highest level, big games - it allowed me to get closer to the best players in the world.
"It is a very special moment because I do not know what my reaction will be. I am quite apprehensive about it," he said of the second leg after the opening match in Istanbul ended in a 1-1 draw.
Jose Mourinho looked close to tears after being given a rapturous welcome by the Stamford Bridge faithful when he returned for his second stint as manager at the start of the season but he believes Drogba deserves even more adulation from the fans.
"I think I'm allowed to say that I will receive a warm welcome because I know Chelsea's fans and our relationship is really special," said Drogba.
"It will be great to see them again. I am looking forward to it."
Mourinho brought Drogba to Stamford Bridge from Olympique Marseille and the pair clearly share a special bond.
"When Chelsea were thinking of signing me it was Mourinho who came to see me," said the 36-year-old forward. "He said, 'If you want to be a great forward like Thierry Henry or Ruud van Nistelrooy you have to come and play for me.
"It's true that I was a good player in the French League at the time but he made me one of the best in Europe. That's why I, for Jose, was capable of going to the ends of the earth."
Drogba's successor as the leader of the Chelsea attack, Fernando Torres, gave his side the lead in the first half in Istanbul.
Galatasaray were outplayed in the opening period but they forced Mourinho's men on to the back foot in the second half and earned a deserved draw thanks to an equaliser from Aurelien Chedjou.
The Turkish team are the underdogs but Chelsea must clear their heads quickly after Saturday's meltdown at Aston Villa.
The Premier League leaders lost 1-0, had Brazil midfielders Willian and Ramires red-carded and Mourinho was also sent from the dugout in the closing stages.
Striker Samuel Eto'o and midfielder Frank Lampard missed the defeat at Villa and could return against Galatasaray in place of Torres and Oscar.
Galatasaray warmed up for the trip to Stamford Bridge by drawing 0-0 at Karabukspor on Friday.
Roberto Mancini's side are second in the Turkish championship, five points adrift of leaders Fenerbahce.
Drogba believes that if Galatasaray are firing on all cylinders they are capable of knocking Chelsea out.
"If we are focused, if we are well physically, then we can make it difficult for many great teams," he said.
(Editing by Toby Davis)