It took a Grand Court jury about an hour to find Dane Damion McPherson guilty of causing grievous bodily harm with intent.
It stems from an incident last year when Mr. McPherson struck a co-worker with a hammer.
Both the prosecution and defense gave closing statements Tuesday (10 April) after more witness testimony.
Mr. McPherson appeared shocked and shaky as the verdict was read.
Justice Michael Wood told Mr. McPherson he will have to go to jail.
Attorneys present told Cayman 27 previous convictions for crimes of this nature drew sentences between four and nine years.
Mr. McPherson was bailed and reappears for sentencing on 17 May.