Eoin was born in Wexford, a picturesque coastal town in the southeast corner of Ireland. Attending the primary school where his father taught, Eoin first developed his interest in writing and began his life long habit of writing his own stories complete with illustrations.

He qualified as a primary teacher in 1986. He began teaching in a local primary school by day but continued to write at night. Eoin rapidly became involved in the local amateur drama group starring in, directing and later writing many award winning productions. His monster best seller Artemis Fowl was published in 2001.

P.J. Lynch has won many awards, including the Mother Goose Award, the Christopher Medal three times, the Irish Bisto Book of the Year Award, and the prestigious Kate Greenaway Medal on two occasions – first for The Christmas Miracle of Jonathan Toomey by Susan Wojciechowski, and again for When Jessie Came Across the Sea by Amy Hest.

In recent years, P.J. Lynch has been commissioned to design posters for Opera Ireland and the Abbey Theatre, as well as designing stamps for An Post. He lives in Dublin with his wife and three children.