The invention relates to a comprehensive utilization method for bittern, which belongs to the technical field of salt chemical engineering. The bittern is a liquid mineral product, and is rich in multiple elements such as potassium, sodium, lithium, boron, bromine, iodine and the like; and at present, in the prior domestic bittern development and utilization, some simple components or components with high additional value in the elements are extracted, and the un-extracted components are discharged along with old bittern to be abandoned so as to cause serious waste of resources and pollute the environment. Through reasonable combination of processes of removing H2S from the bittern, settling magnesium, settling calcium and preparing calcium carbonate, preparing potassium-sodium mixed salt through primary salt preparation and secondary salt preparation, extracting potassium chloride through flotation, extracting boron, iodine, bromine, rubidium and cesium through acidification, preparing rubidium chloride and cesium chloride, extracting lithium and the like, the method implements step-by-step ordered extraction of main components; the toil yield of several main components reaches over 95 percent; and the method has the advantages of mutually exclusive loss in component extraction, implementation of closed cycle of processes, no mother liquor discharge, simple process control, low cost, high yield, environmental protection and the like.