“Southern Hospitality” star Grace Lilly was arrested Tuesday … and it looks like drugs were allegedly involved.

According to new legal docs, obtained by TMZ, Grace was busted for possession of a controlled substance.

It appears Gracy has already been released from custody.

It’s the second time in three months Grace has been arrested in South Carolina … as we first told you, she got busted back in December in Charleston.

In that first arrest, Grace was busted on a warrant after being pulled over for an alleged traffic violation … and cops say they found “happy pills” in her purse.