The consequences of mass and energy conservationand the laws of thermodynamics for economic activity areanalysed. As the objectives, for this content of the relationsbetween thermodynamics and economics is criticallyinvestigated. First, the relations between mass and energyconservation and the Laws of Thermodynamics arediscussed. Then the analysis of neoclassical economicsattitudes to the Laws of Thermodynamics is given. Afterthis the analysis of the concept of weak sustainability andthe Laws of Thermodynamics are discussed. Methods ofsystematic scientific literature analysis, general andlogical analysis, comparison and generalization were usedas the methods of the research.