Serio

Serio may refer to:
 * Sério, a municipality in Rio Grande do Sul, Brazil
 * Serio (river), a river in Lombardy, Italy
 * Cascate del Serio
 * 11022 Serio, a main belt asteroid

People with the surname

 * José Sério (1922–2010), Portuguese footballer
 * Renato Serio (born 1946), Italian composer, conductor and arranger
 * Steve Serio (born 1987), American wheelchair basketball player

Fictional

 * Serio (HMX-13), a character from the visual novel To Heart