Photometric observations of this asteroid gave a light curve with a period of 13.623 hours. The data was used to construct a model for the asteroid, revealing it to be a regular-shaped object, spinning about a pole with ecliptic coordinates (β, λ) = (+20°, 356°), although this is with an accuracy of only ±10°. The ratio of the major to minor axes lengths is roughly equal to 1.2. It is classified as an S-type asteroid and has an estimated size of 154.34 km. The spectrum of 354 Eleonora reveals the strong presence of the mineral Olivine, a relatively rarity in the asteroid belt.