Niobium is a gray white metal with a melting point of 2468 ° C, a boiling point of 4742 ° C, and a density of 8.57g/cm3. Niobium is a glossy gray paramagnetic metal. High purity niobium metal has high ductility, but hardens with increasing impurity content.

Niobium exhibits superconducting properties at low temperatures. At standard atmospheric pressure, the superconducting critical transition temperature T of niobium is 9.25K, which is higher among all metals with superconducting properties. Its magnetic penetration depth is also higher among all elements. Niobium is one of the three types of element type II superconductors. The purity of niobium metal has a significant impact on its superconducting properties.

The thermal neutron capture cross section of niobium is very low, making it very useful in the nuclear industry.