A process for the stabilization and disinfection of sludge wherein a) raw sludge having a dry matter content of from 3 to 7% by weight is fed continuously or quasi-continuously into a first stage, where it remains for an average retention time of three to ten days under aerobic-thermophilic conditions to obtain a partially stabilized sludge; and b) the partially stabilized sludge is fed into a second stage in which disinfection of the partially stabilized sludge is effected at temperatures of at least 50.degree. C., wherein prior to discharging, there is no charging until the partially stabilized sludge has been disinfected.