DaMarcus Beasley's first goal for Rangers made sure of a place in the Champions League's third qualifying round at the expense of Zeta.
DaMarcus Beasley scored Rangers' only goal in Montenegro
Beasley fired wide early on, while Allan McGregor saved easily from a low Bojan Ivanovic drive at the other end.
But Rangers were content to subdue the Montenegrin champions.
They escaped a decent penalty claim when Kirk Broadfoot challenged Slaven Stjepanovic, but Beasley's 80th-minute strike ensured a 3-0 aggregate win.
Rangers will play either Red Star Belgrade or Levadia Tallinn in the next round of the competition.
The second leg of that tie takes place on Wednesday, with Belgrade leading 1-0 ahead of their trip to Estonia.
Kris Boyd had started on the bench for Rangers in Montenegro after picking up an ankle injury against Inverness on Saturday.
Jean-Claude Darcheville was given a central role up front, with Lee McCulloch and Beasley on the wings for support.
Kirk Broadfoot deputised for suspended right-back Alan Hutton.
But the Rangers defence looked comfortable early on, allowing the Glasgow side to create the first chance.
Beasley burst through the centre but sent his powerful drive a few yards wide from the edge of the box.
Zeta were being restricted to long-range efforts, although the impressive Stjepanovic and Marco Cetkovic were controlling midfield - just as they had in the first leg at Ibrox.
And, when Cetkovic's strength took him past a couple of challenges, Bojan Ivanovic sent a low drive towards goal from just inside the area that McGregor did well to gather.
Slaven Stjepanovic claimed for a penalty in the second half
Nenad Djurovic, who had replaced Milan Vuckovic in the Zeta defence from the team that contested the first leg, was lucky to escape with a booking for a reckless challenge on Lee McCulloch early in the second half.
By that time, Rangers had largely stamped out the threat of Stjepanovic and Cetkovic but were happy to sit back in an attempt to kill the game.
However, McGregor did well to come off his line to punch the ball off the head of Stjepanovic on the edge of the box.
Nacho Novo replaced Darcheville and the Spaniard's pace allowed Rangers some respite and renewed their own goal threat.
McCulloch sent a drive wide from 20 yards then headed just over after Novo had sent the ball high across goal.
Broadfoot, who had been booked early in the second half, was lucky not to concede a penalty after 75 minutes.
He appeared to challenge Stjepanovic late on when challenging for a cross into the penalty box and the Zeta midfielder was booked for his protests to referee Paolo Dondarini.
But Rangers killed the tie when Beasley cut inside to weave past a couple of challenges before driving the ball low into the near corner from 20 yards.
Zeta: Sasa Ivanovic, Igumanovic, Radulovic, Miroslav Kaludjerovic, Bojan Ivanovic (Boljevic 70), Markovic, Cetkovic, Tumbasovic (Vuckovic 84), Djurovic (Knezevic 56), Stjepanovic, Korac.
Subs Not Used: Mustur, Marinkovic, Vladen Pelicic, Zarija Pelicic.
Booked: Igumanovic, Djurovic, Stjepanovic.
Rangers: McGregor, Broadfoot, Weir, Papac, Cuellar, Ferguson, Hemdani, Thomson (Adam 87), Beasley, McCulloch, Darcheville (Novo 61).
Subs Not Used: Carroll, Boyd, Gow, Murray, Sebo.
Goals: Beasley 81.
Ref: Paolo Dondarini (Italy).