In order to develop strategies for reducing greenhouse gas emissions (GHGE) from agriculture, the production systems have to be analyzed in a first step. The aim of this study was to to quantitatively assess the GHGE from typical Austrian beef and lamb production systems. Via model calculations, the production systems bull fattening (intensive), bull fattening (semi-intensive), oxen (steer) fattening, heifer fattening, suckler-beef production, cull cow fattening, lamb fattening (intensive) and lamb fattening (pasture-based) were analyzed. Related to various product units (per kg carcass, per kg of meat, etc.), lamb production systems show higher GHGE than beef production systems. The lower carcass yield and the lower meat proportion of the lambs are important reasons for these results. Bull fattening systems show the lowest GHGE per product unit. They are characterized by high growth intensity and good carcass yield with a high meat proportion. The GHGE from the mother (dairy cow, suckler, ewes) are also a very important influencing factor. Calf rearing in dairy production systems results in an advantage over suckler systems, because a great part of the GHGE from the dairy cow can be attributed to the milk production. If steers, heifers and bulls originate from the same rearing systems, the GHGE of the different beef production systems are at a similar level. Stocking density is an important factor for the GHGE per hectare of farmland. Extensive production systems therefore show lower GHGE per hectare. In all systems, enteric fermentation is the main source of GHGE. Due to the higher digestibility of the diet, systems with higher feeding intensity show lower GHGE from enteric fermentation. In contrast, extensive production systems show lower GHGE from farm manure, fuel consumption, fertilizer and pesticide use and land-use change.