Conwy Council warned that future offenders may be named and shamed.
A spokesman for the Welsh council said that the employee chose to disregard both the law, which came into force in Wales on April 2, and his employer's instructions.
A council enforcement officer had spotted the driver, who was employed by a private company, "smoking in a place of work."
On July 1, England followed Wales, Scotland and Northern Ireland in banning smoking in enclosed spaces.
Last week former Liberal Democrat leader Charles Kennedy was "spoken to" by police for smoking on a train from London Paddington to Plymouth.
On Thursday the House of Commons was also told other MPs were not obeying the new smoking ban.
Although not illegal in the Palace of Westminster, both Houses of Parliament agreed to restrict smoking to four designated outside areas, although those caught smoking will not face financial penalties.