The formation of marine potash salts needs a coupled mechanism of tectonics, palaeoclimate, and source. Tectonic element is the primary controlling factor. A sequence of marine evaporites was developed in the Late Sinian–Early Cambrian Dengying Formation in South China Block (SCB). An integrated literature analysis of the position of continents, palaeo-altitude, palaeoclimate, palaeogeography, and seawater chemistry indicates that the SCB should be an integral part of Gondwana close to the northwestern margin of India. Deposits of the Dengying Formation are similar to those in India, Pakistan, Oman, and Iran. These deposits were deposited in a giant carbonate platform. Shallow restricted marine evaporites were developed in the carbonate platform with the highest temperature up to about 40℃. A comparison of tectonic and sedimentary setting between SCB and Salt Range indicates that the evaporite-bearing Dengying and Salt Range formations were deposited in a shallow marine environment on the northern margin of the Gondwanaland passive continent and shared the similar evaporitic sequence and formation conditions. It is thus inferred that the Dengying Formation in the SCB has the essential conditions for the formation of potash deposits.