Abstract: As an important method of Side Channel Attacks (SCA), fault attacks offer the attacker plenty of possibilities to attack a cryptosystem, and nearly all the cryptographic algorithms are broken by using such kinds of attacks. So far many countermeasures against fault attacks are proposed. Howerever, most of them have drawbacks such as overhaed and fault coverage. In this paper, a circuit level countermeasure is proposed based on the strong robust of Null Convention Logic (NCL) circuits and dual-rail encode. The experimental evaluations show this countermeasure offers advantages on fault detecting capabilities and elimates fault propagation with lower cost, and it can be applied to kinds of automatization synthesis techniques.