The hosts came flying out of the blocks and raced into a third-minute lead.
Adam Reach delivered an inviting cross from the left which was powerfully headed to the roof of the net by Cristian Lopez, a first goal in English football for the Spanish striker on loan from Huddersfield.
It set the tone for a dominant first-half display from Shrewsbury who were denied further success by a couple of fine saves from goalkeeper Sam Walker, who did well to hold on to Dave Winfield's volley and Jon Taylor's 25-yard piledriver.
Colchester had offered no threat until they pulled level out of nothing two minutes before the break.
The two sides cancelled each other out for long stages of a second half largely devoid of goalmouth action.
But Gavin Massey came close to a late winner for the visitors when he fired just wide from the edge of the box.
- Sports & Recreation
- Dave Winfield