The Minister of the Left (左大臣, Sadaijin)[1] was a government position in Japan during the Asuka to Meiji era.

The Asuka Kiyomihara Code of 689 marks the initial appearance of the Sadaijin in the context of a central administrative body called the Daijō-kan (太政官, Council of State).

[1] This early Daijō-kan was composed of the three ministers—the Daijō-daijin (太政大臣, Chancellor of the Realm), the Sadaijin and the Udaijin (右大臣, Minister of the Right).

When the Emperor and the nobility held real power, the Sadaijin was the highest permanent position in the Daijō-kan, the central organ of the state.

[3] The Sadaijin was the Senior Minister of State, overseeing all functions of government with the Udaijin as his deputy.