Caesium permanganate is the permanganate salt of caesium, with the chemical formula CsMnO4.

Caesium permanganate can be formed by the reaction of potassium permanganate and caesium nitrate: Caesium permanganate is soluble in water with a solubility of 0.97 g/L at 1 °C,[2] 2.3 g/L at 19 °C, and 12.5 g/L at 59 °C.

Similar to potassium permanganate, the two-step decomposition of caesium permanganate leads to the formation of caesium manganate intermediates.

It breaks down into manganese dioxide, caesium oxide and oxygen.

[6] Drift-away oxygen caused an 8% mass loss in the product.