Almost all Erasmus students receive a mobility grant. The allocated amount depends on your university. This is an average of 100 euros per month for the duration of your studies. You must submit your grant pursuant to your current university. Warning: the first installment of the grant several months may be effective after your departure.
There are various scholarships available online for particular schools, certain degrees, graduate/doctor/PhD students or students looking for grants for research in Spain.
Also, if you do not participate in an exchange program, you can apply for a grant from Spain through the The Ministry of Education. www.mecd.gob.es/educacion/becas-y-ayudas.html