Soulja Boy woke up to some heartbreaking news ... some heartless saps broke into his beloved SODMG flagship store in L.A., and TMZ Hip Hop has the ghastly aftermath -- of the $25K worth of damages!!!

See our footage from the scene for yourself ... disrespectful thieves went straight through the front door of Soulja's store -- without a key, leaving mounds of broken glass on the ground on Melrose.

The store's boarded up for the day ... and adding insult to injury, there's already a fresh coat of graffiti on the entrance door.

It also appears bolt-cutters were used to loosen the locks, causing some red paint to chip off onto the steel ... either that or the cops are gonna have an easy case to crack once the DNA samples return!!!

A source close to the situation tells us thieves made away with exclusive Soulja Boy merch, including shirts, hoodies, hats, and one-of-a-kind Bearbricks.

Other swindled items included Soulja Boy's memorabilia custom leather jacket, and even a PlayStation.

We're told the team has since hired a 24-hour patrol service to watch the store from here on out.

The last time we spoke to Soulja Boy at his store, he was focused on buying TikTok, not identifying criminal masterminds trying to turn his swag off.