This trained master car mechanic from Altingen in the district of Tübingen began his long career in motorsport with slaloms and hill climbs, which he did more as a hobby. In 1981, he won the title of German Mountain Champion, and in 1983 the German Racing Trophy. From 1987 to 1989, he continually achieved further successes: as a three-time winner of the Porsche 944 Turbo Cup and in 1989 additionally as winner of the German Porsche Carrera Cup.
After a brief stint in the German Production Car Championship in 1984 and two years of racing with the Ford Ringshausen Team, Asch became a Mercedes-Benz works driver in the DTM in 1988. Already in his premiere year, when he started for BMK-Motorsport, he managed to finish second overall in his Mercedes-Benz 190 E 2.3-16 Group A. In 1989, he finished tenth in the championship in a 190 E 2.3-16 DTM and later in a 190 E 2.5-16 Evolution DTM of Team MS-Racing. In 1990, he had to be content with 21st place overall in a 190 E 2.5-16 Evolution DTM in the Snobeck Racing Service team, while in the following two seasons he returned to his old strength with the 190 E 2.5-16 Evolution II DTM in the Zakspeed team, finishing ninth and sixth in the drivers' standings.
In 1993, Asch started in the AMG-Mercedes team in both the familiar 190 E 2.5-16 Evolution II DTM and, later in the season, in the new 190 E Class 1 DTM, which held up the Mercedes-Benz flag with flying colours until the arrival of the C-Class DTM with a V6 power unit. In the interim model, Asch secured second place in the championship against the toughest competition, which he followed up with sixth place in the final drivers' standings in the 1994 season in the new C-Class DTM.
From 1995 onwards, Asch turned to the Super Touring Car Cup and later back to the Porsche Carrera Cup and subsequently only competed in a few races in different makes. Roland Asch is occasionally on the road for Mercedes-Benz Classic as a Brand Ambassador in historic sports and racing cars from the company's own vehicle collection. The Swabian's main job is looking after his car dealership in Ammerbuch, south of Stuttgart.