Spain has lost more than 28,400 people to the pandemic so far.
King Felipe on Thursday gathered with EU heads, Spanish politicians and the families of victims to honour all those who have died, as well as those who continue to work against the virus.
About 400 participants came to the Royal Palace in Madrid and sat in socially distanced chairs in concentric circles around a flame.
People wore black face masks and placed flowers around the fire.
Hernando Maria Calleja, brother of the journalist Jose Maria Calleja who died of Covid-19, told the audience that the virus was a "cruel, destructive, cold killer".
"I believe that my pain resembles the pain of each and every one of the relatives of the victims.