It was first revealed that the Scottish Premiership side would go up against Progres Niederkorn of Luxembourg in the opening stages of the competition.
Should they come through the two-legged tie, they will be paired with either Cypriot outfit AEL Limassol or St Josephs FC of Gibraltar.
After finishing in third place in the league standings last season, Rangers will have to come through four ties if they are to reach the group stages.
Fellow Scottish outfit St Johnstone also featured in the first qualifying round draw, where they learned that they will play Lithuania's FK Trakai, with the victors going on to face either Sweden's IFK Norrkoping or FC Prishtina of Kosovo.
Aberdeen received a bye through to the second qualifying round, where they will meet either Kazakhstan's Ordabasy Shymkent or NK Siroki Brijeg of Bosnia and Herzegovina.