The article describes the complex of knowledge and beliefs associated with representations of the planet Venus as the Goddess Inanna/Ishtar in ancient Mesopotamia from the to the early 2nd millennium BCE. The following groups of sources are analyzed: 1) the earliest pictographic texts from archaic Uruk, which combined the symbol of Inanna with astral symbols; 2) various references to Inanna in cuneiforms with astral meanings; 3) visual representations of Inanna as astral goddess in ceramics, sculpture and architecture; 4) Inanna’s role in the Sumerian pantheon, in masculine and feminine versions; 5) observations of Venus in the time of Ammitsaduka.