Kleemann A/S is an after-market tuning company for Mercedes-Benz sports cars, sedans, and SUVs headquartered in Farum, Denmark.

Kleemann's slogan is "Comfort Power," referring to its low-boost, high-output engines that create substantially more power than standard Mercedes models. Kleemann vehicles also include structural and mechanical integrity improvements often lacking in tuned sports cars. It's corporate logo is an abstract arrow which some corporate representatives refer to as the Kleemann carrot.

Any vehicle on the Mercedes lineup can be tuned in a number of ways from SLK roadsters to G-Class Wagons. Customers can specify custom seats, floormats, and interior fabrics as well as carbon fiber body kits, carbon front and rear splitters, and carbon interior panelling. Customers can order simple ECU upgrades that change transmission shift times and valve timing, or they can more aggressively have the engine bored and supercharged, install camshafts and high-flow headers. Kleemann also manufactures its own racing wheels, racing LSD's, racing suspension components, and multi-piston brakes. Kleemann can even install Lamborghini-style vertical doors on their modified vehicles