Javier López Vallejo (born 22 September 1975) is a Spanish footballer who plays for Kavala F.C. in Greece, as a goalkeeper.
Born in Pamplona, Navarre, López Vallejo began his career at hometown CA Osasuna, making his first appearance for the main side not yet 19, on 15 May 1994, in a 3–0 home win over Sporting de Gijón, although the Navarrese side was already relegated. He became an undisputed starter from 1995–96 onwards.
He signed for Villarreal CF in 1999, alongside teammate Jesús Unanua (also a goalkeeper), appearing in all the matches during 1999–2000, as the side returned to the topflight after a one-year absence, and maintaining first-choice status the following two seasons.