Niobium is a shiny gray metal with paramagnetic properties. High purity Niobium has a high ductility, but it becomes harder with the increase of impurity content. Niobium behaves as a superconductor at low temperatures. At standard atmospheric pressure, it has a critical temperature of 9.2K, which is the highest of all elemental superconductors. Niobium also has the highest magnetic penetration of all the elements. Niobium has a very low thermal neutron capture cross section and therefore is used in large quantities in the nuclear industry.

The chemical properties of Niobium are very similar to Tantalum. Although the corrosion resistance of Niobium is not as high as that of Tantalum, the price is competitive, so it is often used to replace Tantalum in less demanding situations, such as as coating material in chemical tanks.