The Congress is the governmental deliberative body of Sonora, which is equal to, and independent of, the executive.

Deputies are elected to serve for a three-year term.

Since its installation the congress has been renewed 63 times, hence the current session of the Congress of Sonora (whose term lasts from 2021 to 2024) is known as the LXIII Legislature.

The LXIII Legislature of the Congress of Sonora consists of 33 deputies.

Since 1917 the Congress has been composed as follows: María Jesús Guirado Ibarra [es] was elected the first female member of the Congress of Sonora in 1955, which was the first election after the passage of women's suffrage in Mexico.