Verdict
Yes — you can hold India and Spain citizenship simultaneously.
India
Dual citizenship policy
OCI card (not full dual citizenship) — grants lifelong residency, work, study, and property rights in India but NOT voting rights, public office, or Indian passport.
Spain
Dual citizenship policy
Permitted for descent and Memory Law applicants. Spain generally requires renunciation for naturalized citizens, but this is not enforced for Ibero-American/Sephardic descent.
Both India and Spain permit dual citizenship. You can acquire, hold, and use both passports simultaneously without legal restrictions.
This assessment is based on each country's current nationality law. Dual citizenship rules can change — always verify with the relevant consulate or an immigration attorney before making decisions about renunciation or acquisition.