The invention provides a stuffing box radio frequency coaxial cable water-stop adapter device. The radio frequency coaxial cable adapter device comprises a sealing flange, socket stuffing box sealing structures, oil seal structures and cable insulating dielectric layer stuffing box sealing structures. The adapter device is in sealing connection with a sealed container through the sealing flange, two rectangular sealing grooves and two sealing rings. Each sealing stuffing box comprises one socket stuffing box sealing structure, one oil seal structure and one cable insulating dielectric layer stuffing box sealing structure. The radio frequency coaxial cable adapter device effectively improves the water sealing performance of adapter coupling of a radio frequency coaxial cable under the polyelectrolyte water pressure and is applicable to transmission of very high frequency signals or ultrahigh frequency signals.