What is the name of Michelangelo's earliest known marble relief?

Michelangelo’s earliest known marble relief is Madonna of the Stairs.

Usually dated to about 1490–1491, the work belongs to the artist’s teenage years in Florence. It is carved in extremely shallow relief, a technique known as stiacciato that Michelangelo learned from the sculptural tradition associated with Donatello. The thinly cut surface creates depth through subtle changes in level rather than through deeply projecting figures.

The composition shows the Virgin in profile, seated on a stone block and looking away, while the sleeping Christ Child twists across her lap. Small figures of putti occupy the staircase behind them. The relief’s quiet, compressed design already hints at Michelangelo’s later interest in powerful bodies and complex movement, even though the work is intimate and relatively small.

“Earliest known” is important wording: the sculpture is the earliest surviving marble work securely associated with Michelangelo, not necessarily the first object he ever made. The Battle of the Centaurs, created around the same period, is another very early sculpture, but it is a deeper, larger relief rather than this shallow Madonna.