SuGoiSuす語彙すGrammar › N1 · 10 Obligation and prohibition
〜ずにはおれない: cannot help but
N1 · 10 Obligation and prohibition
Says you cannot stop yourself from doing something because the feeling is so strong.
Verb ない-stem + ずにはおれない (する becomes せずにはおれない). Same as 〜ずにはいられない but a little more emphatic and literary. Subject is the speaker. Compare 〜ずにはおかない, where something affects others.
Examples
困っている人を見ると、助けずにはおれない。
When I see someone in trouble, I cannot help helping.
あの話を聞いて、笑わずにはおれなかった。
Hearing that story, I could not help laughing.