It means they are now homing in on a place in the quarter-finals and will complete the pool stages of the competition against Bayonne on Saturday.
But it was a ragged performance against an inspired Bucuresti team who went the distance and then some. They never threatened an almighty upset, but their defensive commitment, relish for the contest and sheer determination shone throughout on a freezing afternoon.
They were also helped by a real bog of a pitch and Gloucester were forced to battle and scrap all the way to subdue the hosts.
It looked to be going to plan as early as the fifth minute when Jake Boer was driven over from a line-out catch by Adam Eustace. But thereafter, Gloucester could establish and then maintain field position long enough to build their lead.
In fact, it was Bucuresti who dominated territory, although they kicked a huge amount of possession which made for a very busy afternoon for Jon Goodridge at full-back.
The fact it remained 5-0 at half-time tells its own story and it needed the big men - Peter Buxton, Jake Boer and Mark Cornwell - to keep Gloucester on the front foot.
It was not until the arrival of Gary Powell at half-time that Gloucester extended their lead. His powerful surge up the middle following a scrum created room for Rob Elloway to surge up on his shoulder, take the pass and score near the posts.
But the 12-0 leasd was not to last. When replacement Catalin Fercu made ground through the middle, he created space and lock Cornel Tatu was on hand to delight the home crowd with the try.
Through the efforts of number eight Cosmin Ratiu, who will be very sore this morning considering his marvellous effort, Bucuresti trailed by five points with 15 minutes of the second half gone.
The introduction of Peter Richards and Ludovic Mercier created more urgency and it was Richards who grabbed the third try when he took Mefin Davies' neat flick pass to score in the corner.
With Bucuresti out on their feet, Gloucester secured the bonus point they so badly needed when the referee awarded a penalty try from a scrum.
But it was not a thing of beauty and Gloucester were glad to hear the whistle and escape with the job done.
"I think you have to give Bucuresti a huge amount of credit for the way they approached the game," said Gloucester's head coach Dean Ryan. "From our point of view there was a quality issue and that came because the team contained a number of players who have not been involved week in, week out.
"It was a very difficult game but we got the bonus point and the job done and that was the most important thing. I appreciate it was not a game of great quality, but our supporters, who were once again superb, played a major part on a difficult afternoon.