The invention relates to a method for the on-line management of energy consumption for multiprocessor systems, the method executing at least one application according to a chart of tasks, wherein the method includes, for each application: a first phase for the off-line characterization of the variation of the potential rate of parallelism of execution of the tasks as a function of time, this characterization being based on the worst-case task execution times; and a second phase for the on-line detection and exploitation of the inactivity intervals and of the potential time excesses. A DPM technique makes it possible to determine the duration of the inactivity interval during which a processor may remain inactive according to the potential rate of parallelism characterized in the worst case.