It was observed that Ba(BrF 4 ) 2 demonstrates a high reactivity towards n-hexane. It was found that the heating the reaction mass proceed with intensive self-heating up to 40°C and release of elemental bromine. The GC-MS analysis showed that the main product of Ba(BrF 4 ) 2 interaction with n-hexane is 3-bromohexane. The optimal interaction parameters were found. The heat effect of the reaction was determined by isothermal calorimetric method, it was –1451kJ/mole. The qualitative composition of solid precipitate was determined by EDXRF and XRD analyses. BaF 2 is formed as only solid product of the reaction between Ba(BrF 4 ) 2 and n-hexane. It was found that conditions of researched reaction are quite unusual for known free-radical hydrogen substitution processes in case of alkanes. Also we can conclude that Ba(BrF 4 ) 2 is much more soft reagent is case of interaction with alkanes in comparison with BrF 3 and it can provide more or less selective bromination of alkane unlikely to BrF 3.