The flag of Treinta y Tres, Uruguay, is rectangular, uses the colors of the Uruguayan flag. It is the official flag of the department since February 7, 2003.
Its design is as follows: on a white background, four blue stripes to the left that symbolize the waters of the department; meaning of the color blue: air and the ideals of justice and truth. To his right, a gold-colored half sun, which represents - eastern department -, light, and the ideals of nobility.- in a circle of purity, the ancient raven, in swift flight, as if challenging the abysses of the Quebrada; it moves away from the zucará in green and red, one of the autochthonous elements of our natural mount. Its color, water - fire, enunciates ideals of freedom, hope, courage and joy. The silver color of the bird means creek bird; it is the earth and the ideals of integrity and purity.