The influence of 10 years reduced tillage (RT) on the potential carbon mineralization of the 0-5 cm layer of silt loam soils in Belgium under a temperate climate was investigated. Therefore, four fields at three locations under 10 years of RT and fields under conventional tillage (CT) with comparable crop rotation were selected. The higher % soil organic carbon in the upper layer resulted in a higher potential carbon mineralization of the RT fields. The small increase in % soil organic carbon and potential carbon mineralization of RT fields was contributed to the high soil disturbance due to incorporation of manure in the upper layer and the production of sugar beets and potatoes. Simulating ploughing by emptying and refilling the soil cores resulted mostly in a higher potential carbon mineralization. However, the differences were not significant due to the high variability in potential carbon mineralization.