400 Ducrosa is a typical main belt asteroid. It was discovered by Auguste Charlois on 15 March 1895 in Nice, and named for It J. Ducros a mechanic at the Nice Observatory. This minor planet is orbiting the Sun at a distance of with a period of and an orbital eccentricity of 0.117. The orbital plane is inclined at an angle of 10.5ð to the plane of the ecliptic.
This asteroid has a B-type taxonomy, indicating it has a relatively bright geometric albedo for a carbonaceous asteroid. It has an estimated diameter of . Photometric measurements of the asteroid made in 2005 at the Palmer Divide Observatory showed a light curve with a rotation period of and a brightness variation of 0.62 in magnitude. A 2020 study found a rotation period of with a variation of 0.57 magnitude.