A punctureproof tubeless, or tube-type pneumatic tire equipped with a series of resilient sacs inflated with gas under pressure, and consisting of individually sealed sac elements fabricated with thin elastic or plastic sheet material conformable with the inner casing and/or tube structure. This sac element arrangement is placed in the usual main compressed gas space of the tire casing, or inner tube and automatically resists any deformation of the casing resulting from a puncture thereof.