Dad-of-two Ted Phillips. who worked at Harworth Colliery before it closed in 2006, drove out to Haxey Church of England Primary School, on The Nooking, after hearing the animal was on the road outside the premises.
He had received phone calls from worried parents who feared for the safety of children.
He caught the 6ft tall bird with help from two dads and was also assisted by a passing police officer who was flagged down by another parent.
Ted, aged 50, originally from near Bawtry, Doncaster, retrained after leaving his mining job and now runs Shepherd's Place Petting Farm, also in Haxey. It has a number of rheas - the South American equivalent of an emu.
He said: "The emu has been said to be running round the Isle of Axholme for the last week, and people have been ringing me up with reports of it, but it was not our bird so I didn't feel there was anything I could do.
"But this morning, I got a phone call saying it was at the primary school in Haxey - the mums were ringing up saying 'we've got an emu running round'. I went down and jumped on it.
"We've got rheas on our farm, and they are slightly smaller than emus. There were two running round Sprotbrough last year, and we re-homed them, so I am used to handling that sort of bird.
"Emus are bigger, but there were safety issues for the children, so I didn't feel I could just leave it any longer, and I felt I had to do something.
"It was at the side of the road, opposite the school, and that's why the parents were worried. I got out of the car, got as close as I could to the emu, and then got hold of its head and body, and pushed it to the ground.
"They have quite strong legs, so two dads held its legs. A passing police officer who I thing someone had flagged down also helped hold it down. There were four of us holding it down and we tied its legs."
A passing builder in a van was also flagged down, and he agreed to help transport the bird back to Ted's farm, while the group continued to hold onto it. It is now being looked after at Shepherd's Place.
He said the policeman told him they had stopped a safety issue that could caused danger on the roads, and added he was grateful for the help of the dads and the policeman.