An automatic levelling system for a work machine able to lift loads, comprising: a plurality of outriggers mobile between a rest position and at least a working position in which the outriggers can rest on a ground surface so as to stabilise said machine, each outrigger including an extensible thrust element able to rest on the ground surface; at least an activating apparatus able to selectively activate said outriggers, able to receive command signals and able to regulate an extension of the thrust element of each outrigger with respect to the ground surface, according to said command signals; at least an electronic measuring device for measuring an inclination, destined to be associated to a reference element of the machine, able to measure the inclination thereof and produce inclination signals as a function of the inclination measured; a processing unit able to receive said inclination signals and comprising a levelling module configured for producing said command signals as a function of the inclination measured by said electronic device, the command signals being able to modify the extension of the thrust elements included in the outriggers; characterised in comprising one or more rest sensors, destined to be mounted on the work machine and able to verify whether one or more of wheels thereof are resting on the ground surface or are raised, and to produce grounded signals as a function of verifications carried out, the processing unit being able to receive said grounded signals and comprising an enabling module configured for activating or disabling the levelling module on a basis of whether said wheels are resting or are raised. a plurality of outriggers mobile between a rest position and at least a working position in which the outriggers can rest on a ground surface so as to stabilise said machine, each outrigger including an extensible thrust element able to rest on the ground surface; at least an activating apparatus able to selectively activate said outriggers, able to receive command signals and able to regulate an extension of the thrust element of each outrigger with respect to the ground surface, according to said command signals; at least an electronic measuring device for measuring an inclination, destined to be associated to a reference element of the machine, able to measure the inclination thereof and produce inclination signals as a function of the inclination measured; a processing unit able to receive said inclination signals and comprising a levelling module configured for producing said command signals as a function of the inclination measured by said electronic device, the command signals being able to modify the extension of the thrust elements included in the outriggers; characterised in comprising one or more rest sensors, destined to be mounted on the work machine and able to verify whether one or more of wheels thereof are resting on the ground surface or are raised, and to produce grounded signals as a function of verifications carried out, the processing unit being able to receive said grounded signals and comprising an enabling module configured for activating or disabling the levelling module on a basis of whether said wheels are resting or are raised.