Mario Vellani Marchi (1895–1979) was an Italian painter and scenic designer.
He attended the Modena Academy of Fine Arts in the early years of the second decade of the 20th century and specialised in engraving.
He came into contact with the second generation of the Burano School through a stay on the island in the same year, and landscapes set there constitute a constant feature of his production.
After 1920, he spent some time in Burano painting landscapes, along with Giuseppe Novello, Francesco Arata, and Bernardino Palazzi.
In scenic design, he painted sets for Il Campiello and I Quattro Rusteghi for the Scala theater of Milan.