Manfred Brunner started racing skiing at the age of nine in the ski club of his hometown Bad Kleinkirchheim . In order to further promote his athletic training, he attended the ski school in Stams in Tyrol . At the beginning of the 1970s, Brunner was accepted into the squad of the Austrian Ski Association (ÖSV). He soon came to his first World Cup appearance , but then started for a long time in the European Cup , where he did not achieve any major success at first. After he was unable to take part in a race due to injury in the winter of 1975/76, his results improved significantly in the next season. He first achieved his first podium in the European Cup with second place in the giant slalom in Villach and then came back to the World Cup, where he finished second in the giant slalom in Furano on February 25, 1977 behind Hansi Hinterseer , thus achieving his best World Cup placement and won World Cup points for the first time. With a further three seventh places in giant slalom at the end of winter, he finished ninth in the giant slalom World Cup in the 1976/77 season . As part of the World Cup final in the Sierra Nevada , he also won a parallel slalom on March 27, 1977, which, however, was not part of the World Cup.
At the beginning of the 1977/78 season , Brunner could not build on the World Cup results of the previous year, which is why he was not nominated for the 1978 World Cup in Garmisch-Partenkirchen . Shortly after the missed World Cup, he reached fourth place in the Chamonix slalom , but this was his last point win in the World Cup. He then started again in the European Cup and celebrated his first victory in the slalom in Haus im Ennstal . In the following season 1978/79 he won two giant slaloms in the European Cup in Villach and Puy-Saint-Vincent . In addition, he finished second in two slaloms, placing him third in the overall European Cup ranking, fourth in the giant slalom ranking and fifth in the slalom ranking. However, he did not succeed in returning to the World Cup team. After Brunner had not achieved any top placements in the European Cup the next season, he switched to the Dutch Association in 1980. However, he remained unsuccessful and finally ended his skiing career.