Selena's Killer -- She'll Stay Locked Up, Despite Reports

Selena's killer could get an early release from prison -- as some websites are reporting -- if she proves her health is deteriorating ... but we know she lacks the proof and will stay locked up.

There are reports Yolanda Saldivar -- who shot and killed the Tejano icon in a hotel in 1995 -- was in declining health due to kidney failure and asked the Parole Board for an immediate release.

But our sources say Saldivar has some medical issues but none serious enough to warrant early release. What's more ... she has NOT even filed a petition for early release.

The 54-year-old murderer isn't eligible for parole until March, 2025.