Niccolai is an Italian surname. Notable people with the surname include:
Armand Niccolai (1911–1988), American football player Comunardo Niccolai (1946–2024), Italian footballer Giulia Niccolai (1934–2021), Italian photographer, poet, novelist and translator Lea Niccolai, Italian Late-Antique historian specializing in religious philosophy and socio-political thought
See also Nicolai (disambiguation), German variant Nicolay (disambiguation), French variant Nikolai (disambiguation) or Nikolay, Slavic forms