To provide a protective cap for an eye joint ferrule also usable as a packing and the eye joint ferrule formed by fitting the protective cap thereto.

This protective cap for the eye joint ferrule is used to protect the seal surface of the eye joint ferrule. An annular flange part is formed on one end outer peripheral surface of a ring part for fitting. The inner diameter of the annular part for fitting is generally equal to the outer diameter of an eye bolt to be inserted therein or a slightly larger than that outer diameter. The protective cap is so formed that the outer diameter of the annular flange part is generally equal to the outer diameter of the seal surface of the eye joint ferrule, and desirably molded with a heat resistant resin material or a rather soft metal material such as copper. The eye joint ferrule for fitting the protective cap thereto is so formed that an annular step part concentrical to a bolt insert hole is formed on the seal surface side or the inner peripheral surface of the bolt insert hole is formed straight.