A series of closo-decaborates and closo-dodecaborates as carbocation salts was obtained by the reaction of Kat(2)[BnHn] (n = 10, 12; Kat = Na, K, Ag) with tertiary alkyl halides (C4H9Cl)-C-t, 1-AdBr, and (C6H5)(3)CCl. The prepared compounds were identified by IR and H-1, B-11, C-13 NMR spectroscopy.