The number of pets needing rescue has been dropping in recent years, with 2015 seeing the lowest number since 2008 when nearly 157,000 cats and dogs were picked up.
Still, pet advocacy group Fundación Affinity says that the number of pets last year is still "very high".
"It is troubling that so many animals continue to be abandoned. It is a structural problem that demands greater intervention and cooperation from all of those involved in prevention, whether public or private," the report states.
Once the animals are taken in, 44 percent of them are adopted out, while 20 percent are returned to the owners who lost them.
The report states that increased use of pet microchips has meant that “each day more animals that were lost are returned to their families”.
Another 14 percent of rescued animals stay with the animal shelters while 10 percent are put to sleep.
While most cats and dogs are found in good health, roughly one in three (30 percent) are sick or injured. And more than a quarter (27 percent) are just puppies or kittens.
Two-thirds are found on the street while the rest are brought into shelters by either the owner or someone else.
The most common reasons given for abandoning dogs or cats was their behaviour as well as that they had “unwanted litters”.
The second most frequent reason was economic factors, while the third was related to the end of the hunting season.
Concern about Spain's abandoned pet population has gained international attention, including from British actress Joanna Lumley, who joined a campaign to fight for better treatment of hunting dogs.