Her death was confirmed by Roberto Monroy, the Secretary of Tourism for the Mexican state of Michoacan, who said she'd passed away in Santa Fe de la Laguna ... the same town where she was born more than a century ago.

A cause of death wasn't announced, but Monroy remembered her as a "tireless woman and life model."

She's come to be known as "Mama Coco" -- named after the Disney/Pixar character of the same name in the 2017 animated film, which is centered around Mexico's Day of the Dead traditions. Mama Coco was voiced by actress Ana Ofelia Murguia.

While the Mouse House hasn't officially acknowledged Caballero as the source material behind its titular character -- her family claims a team from Pixar visited their area, photographed Caballero extensively and lived with them for a while.

The family asserts a lot of the exact buildings and architecture Pixar/Disney documented while doing research for the movie showed up in the film ... and that "Mama Coco" likeness is uncannily similar to Caballero.

With that said, her family stopped seeking recognition/validation from the company some years ago -- even though she's a local legend.

Caballero was a clay craftswoman who made pots and other items ... which she'd sell to locals. She's survived by 3 children, lots of grandchildren and even more great-grandkids.

She was 109.