Based on the rules of designing high performance shale inhibitors, bis- (hexamethylene)- triamine was introduced as a potential shale inhibitor in water-based drilling fluid. The inhibitive properties were evaluated through bentonite inhibition test, cuttings hot-rolling dispersion test and particle distribution measurement. The compatibility with common drilling fluid additives was investigated. Bis- (hexamethylene)- triamine effectively inhibited shale swelling and dispersion, superior to potassium chloride and polyetherdiamine POP230, and was compatible with normal additives in drilling fluid. The inhibitive mechanism was analyzed via XRD, zeta potential measurement, FT-IR, water adsorption test and TGA. The results showed that electrostatic interaction, hydrogen bonding and hydrophobic shielding effect contributed to the inhibition with synergetic effects, whereas the protonation of multi-amine groups played a vital role in the action.