Posada was born in Aguascalientes on February 2, 1852. His father was Germán Posada Serna and his mother Petra Aguilar Portillo. Posada was one of eight children and received his early education from his older brother Cirilo, a country school teacher. Posada's brother taught him reading, writing and drawing. He then joined "La Academia Municipal de Dibujo de Aguascalientes" (the "Municipal Drawing Academy of Aguascalientes"). Later, in 1868, as a teenager he apprenticed in the workshop of Jose Trinidad Pedroza, who taught him lithography and engraving.