This is a list of Spanish football transfers for the summer sale in 2009–10 season. Only moves from La Liga and Segunda División are listed.
The summer transfer window opened on 1 July 2009, although a few transfers took place prior to that date. The window closed at midnight on 31 August 2009. Players without a club could have joined one at any time, either during or in between transfer windows. Clubs below La Liga level could also have signed players on loan at any time. If need be, clubs could have signed a goalkeeper on an emergency loan, if all others were unavailable.