Rishon may refer to:

• Rishonim, an era of Rabbis and Poskim
• Rishon LeZion, a city in Israel
• Rishon model, a preonic model of sub-quark particle physics.

• Alloteropsis eckloniana
• Alloteropsis gwebiensis
• Alloteropsis homblei
• Alloteropsis semialata
• Allotetrahydrodeoxycorticosterone
• Allotetrahydroxycorticosterone
• Allothereua
• Allo-threonine
• Allotinus agnolia
• Allotinus albatus
• Allotinus albicans
• Allotinus albifasciatus
• Allotinus anaxandridas
• Allotinus aphocha
• Allotinus apries
• Allotinus apus
• Allotinus audax
• Allotinus bidiensis
• Allotinus borneensis
• Allotinus brooksi
• Allotinus caesemius
• Allotinus continentalis
• Allotinus corbeti
• Allotinus davidis
• Allotinus dilutus