Abstract: Abstract： On the one hand, in our legislation of civil Lawsuit, the system of defense losingright has not yet established; and on the other hand, the defense system in operation presents some evident defects such as violating the procedure fair principle, reducing the effect of court judgment, and being useless of carrying out the current civil evidence rules. The establishment of the system of defense losingright signifies the reasonable limit of the parties' punishing right, which is propitious to putting into effect the lawsuit fair principle, to avoid the confusion of giving evidences, to hence the lawsuit effect, and to realize the double value targets of the "justness and efficiency". Since the foreign system of the defense losingright has sufficiently been proved reasonable in its practice, it is necessary, by reference to the British and American law system and using it as the legislation model of the important documents of carrying out the defense right, to construct our civillawsuit system of the defense losingright in accordance with our practice. And, at the same time, the legal right of the accused should be paid an attention to.

Key words: lawsuit assault, procedure fair, right protection, Key words： defense losingright