Polonium is a highly reactive element and readily forms compounds with other elements. Some of the elements that polonium is known to combine with include:

- Oxygen: Polonium forms various oxides, including polonium dioxide (PoO2), polonium trioxide (PoO3), and polonium tetroxide (PoO4).

- Hydrogen: Polonium reacts with hydrogen to form polonium hydride (PoH2).

- Halogens: Polonium forms halides with all of the halogens, including polonium fluoride (PoF2), polonium chloride (PoCl2), polonium bromide (PoBr2), and polonium iodide (PoI2).

- Alkali metals: Polonium forms alloys with alkali metals, such as polonium-sodium (Po-Na), polonium-potassium (Po-K), and polonium-rubidium (Po-Rb).

- Alkaline earth metals: Polonium forms alloys with alkaline earth metals, such as polonium-magnesium (Po-Mg) and polonium-calcium (Po-Ca).

- Transition metals: Polonium forms alloys with various transition metals, including polonium-iron (Po-Fe), polonium-cobalt (Po-Co), and polonium-nickel (Po-Ni).

- Metalloids: Polonium forms alloys with metalloids, such as polonium-silicon (Po-Si) and polonium-germanium (Po-Ge).