Zaidi may refer to:
- The Zaidi fiqh (Islamic jurisprudence), also known as Zaidiyyah
- Al-Zaidi, Arab descendants of Zaid bin Ali (note: Al-Zaidi may also refer to adherents to the Zaidiyyah fiqh)
- Zaidi Wasitis, people with the surname Zaidi, South Asian descendants of Zaid bin Ali
- Zaidis, South Asian followers of Twelver imams and Ja'fari jurisprudence
- Yiddish informal title for grandfather