In Kantian ethics， the conscience is always a controversial concept. Is the conscience rational or affective？ Does the conscience belong to intelligent deliberation or intuitive response？ Generally there are two opposite interpretations： rationalism and sentimentalism. This paper puts forward a point reconciling them： the conscience in Kantian ethics should be a moral intuition fusing reason and feeling. The conscience is the product of judgment， at the same time it belongs to a general practical reason， but radically it is still a moral feeling including reason and feeling. As a moral intuition， the conscience is best grasped from a point of naturalism. In practical operation， the conscience has the advantage of rapidness and acuteness， but will lead to vagueness and divergence for various reason.