More than 150 of the dead have been found around Valencia, but fatalities have also been confirmed in the regions of Castile-La Mancha and Andalusia.
The floods are the deadliest in over 50 years in Spain.
The search for missing persons since the disaster began on Tuesday continued on Thursday. The death toll may rise as many people are still missing, warn authorities.
Anger grows
Meanwhile, public anger is growing over the delayed issuance of disaster warnings.
As early as Sunday, two days before the floods occurred, Spain's Meteorological Institute Aemet warned of heavy rainfall in the area. Early on Tuesday, the institute issued a red warning, the highest warning level for the effects of the disaster.
But the Civil Defense Authority, which is responsible for national disasters, did not issue a warning until after 8 pm on Tuesday evening local time, and by then several places in Valencia had been flooded for several hours.
Rain continues
And more rain is expected in the region. In the province of Castelló, which borders Valencia, the rain is expected to continue pouring down. Aemet has issued an orange warning.
Prime Minister Pedro Sánchez urges residents in the affected areas to stay at home.
Right now, the most important thing is to save as many lives as possible, he says according to AFP news agency.
Over 150 roads have been damaged by the floods and many are destroyed and closed – which hinders the rescue efforts.
The government has called in more than 1,200 soldiers to help with rescue and sanitation efforts.
Since Tuesday, around 3,400 rescue operations have been carried out in areas affected by the disaster. About 300 people are still cut off from the rest of society due to flooded or damaged roads.
Several municipalities lack drinking water and around 75,000 people lack electricity in the province of Valencia as a result of the storm, writes the Spanish newspaper El Mundo.
