PROBLEM TO BE SOLVED: To provide a neutrophil activation regulator and a therapeutic agent for a disease caused by neutrophil activation. A thrombin-like enzyme is used as an active ingredient of a neutrophil activation regulator and a therapeutic agent for a disease caused by neutrophil activation. [Selection diagram] Fig. 6【課題】好中球活性化調節剤及び好中球活性化に起因する疾患の治療薬を提供する。【解決手段】好中球活性化調節剤及び好中球活性化に起因する疾患の治療薬の有効成分として、トロンビン様酵素を使用する。【選択図】図6