The paper considers the hypotheses for the formation of the primary Earth's crust. It is shown that in the southern part of the Aldan Shield early Archean rocks corresponding to basalts, which can be considered as the remains of the ancient crust have been found. Based on the materials of various researchers, it is assumed that the primary Earth's crust had a basaltic composition. Initially, the Earth was covered with tholeiitic basalts, possibly erupted from the upper mantle. This happened during the planet formation. It is quite possible that the basaltic layer formed on the surface of the Earth during the formation of the core and mantle. After 0.5 billion years – after the formation of the basaltic layer – as a result of tectonic processes, the proto-crust was destroyed. At the same time, 3.57 billion km3 of detrital material was washed away, which replenished the sedimentary layer originating from the biota. During the subsequent billions of years of the earth's existence, accumulation of terrigenous-sedimentary and organogenic material and its transformation into various rocks took place, resulting in the formation of a continental crust with a granite layer. According to electron microscopic studies, it has been found that quartz in Precambrian gneisses, quartzites and other rocks was metasomatically transformed from biogenic limestone rocks. Based on this, an assumption about the formation of the granite layer of the Earth's crust as a result of the hypergenesis of material coming from the destroyed primary proto-crust of the territory of modern oceans into water bodies located in the place of modern continents has been made.