The 1940 Constitution of the Latvian Soviet Socialist Republic (Latvian: Latvijas Padomju Sociālistiskās Republikas Konstitūcija; Russian: Конституция Латвийской Советской Социалистической Республики, romanized: Konstitutsiya Latviyskoy Sovetskoy Sotsialisticheskoy Respubliki) was adopted by the 2nd session of the People's Saeima of Latvia on August 25, 1940.

Two days after the formation of the Latvian SSR on 21 July 1940, which was formalized by the Decree of the Supreme Soviet of the USSR "On the Entry of the Latvian SSR into the Soviet Union" on 5 August 1940,[4] the People's Saeima of Latvia formed a commission for the constitution of the Latvian SSR, which consisted of 15 deputies headed by Žanis Spure [lv].

The final constitution symbolizes "the tremendous upsurge of the masses who overthrew the exploiting classes".

[6] The constitution itself was approved by acclamation in the 2nd session of the People's Saeima of Latvia on August 25, 1940.

The constitution was first published on the News of the Presidium of the Supreme Council of the Latvian SSR (Latvijas PSR Augstākās Padomes Prezidija Ziņotājs) on 3 October 1940.