"I’m proud to be playing for a big and ambitious club like Feyenoord," Javi Lopez said on Feyenoord's club website.
"I can’t wait to join the squad, because I want to make a contribution to the club, my teammates and the supporters as soon as possible. I’ll give my all in this shirt so that, together, we can enjoy some great moments and successes."
Javi Lopez has made 137 total league appearances, of which 80 for Alaves. The defender joined Real Sociedad in 2024 and played 29 LaLiga games in his first season in the Basque Country, but was loaned out to Real Oviedo last season, where, in 26 appearances, he couldn't prevent relegation to the second tier.
Across his 137 league appearances, Lopez scored once and provided four assists.
Javi Lopez joins Feyenoord as their fifth summer signing. Two Spaniards joined the Rotterdam club before him this summer, with striker Nacho Ferri joining from Belgian side KVC Westerlo and defender Mika Marmol joining on a free transfer from Las Palmas.