Bjornerud recalled the story Wednesday when he announced that he is stepping down as agriculture minister.
"I remember walking up the steps of the leg and I'd never been there and I had a briefcase that had nothing in (it) because I wanted to look important," Bjornerud told the Saskatchewan Association of Rural Municipalities convention (SARM) in Regina.
"I got to the guard ... and he said, 'What are you doing here?' I think June Draude was with me because she didn't know where she was going either, and we walked up there and we said, 'Well, we're Liberal MLAs. 'Oh,' he said, 'you go here, here and here.'
"And you know we were lost for about two years in there."
Bjornerud, 66, was first elected as a Liberal in 1995 to represent the constituency of Saltcoats, now Melville-Saltcoats. He went on to become one of the founding members of the Saskatchewan Party.
Bjornerud has been agriculture minister since the Saskatchewan Party first came to power in 2007.
He said some days he wishes every farmer in the province could have the opportunity to be minister of agriculture.
"It's a real experience," he said.
"You know we have some really good days and then, oh my God, we have some bad days. But the good days lately have certainly outweighed the tough days."
Bjornerud said he's getting a little long in the tooth and he wants to spend more time with his six grandchildren. That's tough to do when ministerial duties keep him on the road, he said.
"I love grandkids. You can have them come and visit, you can wind them up and you can send them home," he joked.
"And I know my daughter in Eston will just appreciate that to no end."
SARM president Dave Merit said he was shocked by the announcement. Merit said Bjornerud has been a friend to rural municipalities.
"And I would have to say that Minister Bjornerud will down in history as probably, if not the best, one of the best ag ministers this province has ever had," said Merit.
Bjornerud has dealt with drought, flooding and BSE. He said he's proud of the change to reduce the education portion of property tax on farmland and feels changes still need to be made to improve crop insurance.
He plans to continue sitting as an MLA and will stay on as minister until Premier Brad Wall makes a cabinet shuffle this spring.
Wall paid tribute to Bjornerud, noting that he is currently the long-serving provincial agriculture minister in the country.
"When Bob told me that he wanted to step down from cabinet at the next shuffle, I wasn't surprised because Bob is very, very, very old," joked Wall. "No, I was surprised because of the passion that he had for the work and the job that he has done and the changes that he has made with respect to the ministry."