Pedro I may refer to:
- Pedro I Fadrique (died in 1355)
- Pedro I of Portugal (1320–1367)
- Pedro of Castile (known as The Cruel) (1334–1369)
- Pedro I of Kongo (ruled 1543–1545)
- Pedro I of Brazil (1798–1834)
- Brazilian ship Pedro I
See also
- Peter I (disambiguation)
pl:Piotr I