NOVELTY - The process comprises subjecting garbage or wastes to compression (14) to separate into a putrescible fraction (15) in the form of pulp having a relative humidity of greater than 50% and a dry fraction (10%) (16) having relative humidity of less than 20%, subjecting the putrescible fraction to an anaerobic fermentation treatment (17) to produce a biogas (18), and transforming a part of the dry fraction to endothermic gasification treatment in which a quantity of energy in the form of heat is supplied. The endothermic gasification process is carried out in a gasification reactor.    USE - The process is useful for treating garbage or wastes including household wastes, agricultural wastes and food industry wastes.    ADVANTAGE - The process is capable of easily and economically treating the garbage or wastes, and allows safe recovery and disposal of wastes without polluting the environment.    DETAILED DESCRIPTION - The process comprises subjecting garbage or wastes to compression (14) to separate into a putrescible fraction (15) in the form of pulp having a relative humidity of greater than 50% and a dry fraction (10%) (16) having relative humidity of less than 20%, subjecting the putrescible fraction to an anaerobic fermentation treatment (17) to produce a biogas (18), and transforming a part of the dry fraction to endothermic gasification treatment in which a quantity of energy in the form of heat is supplied. The endothermic gasification process is carried out in a gasification reactor at 700-900 degrees C with combustion oxidizing gas of 6000 m3 per ton to produce a synthesis gas composition comprising a combustible gas. A part of the quantity of calorific energy in endothermic gasification treatment is produced by combustion outside the gasification reactor. A step of extraction of neither putrescible nor combustible inert materials is carried out before the separation of fractions. The separation of the fractions is carried out at a pressure of greater than 750 bars. A compression chamber is fixed with extrusion orifices through which the putrescible fraction flows.    DESCRIPTION OF DRAWING(S) - The diagram shows a flowchart of a process for treating garbage or wastes.    Compression (14)    Putrescible fraction (15)    Dry fraction (16)    Anaerobic fermentation treatment (17)    Biogas. (18)