Juan Manuel "Juanma" Lillo Díez (born 3 November 1965) is a Spanish football manager, currently assistant coach at Premier League club Manchester City.
Having started coaching before his 20s, he was the youngest manager in charge of a La Liga club, having taken over Salamanca at not yet 30 years of age. He also coached Oviedo, Tenerife, Zaragoza and Almería in the top-flight, and had spells in charge of clubs in Mexico, Colombia, Japan, China and Qatar.