Shia LaBeouf's Drinking Problem -- Actor Seeks Treatment for Alcoholism

Shia LaBeouf is NOT in rehab ... but he IS getting treatment for alcohol addiction ... TMZ has learned.

Shia's rep tells us ... reports that he entered a rehab facility are bogus. She says his bizarre conduct over the last few months is symptomatic of a larger health issue -- alcohol addiction -- and he understands it.

It sounds like Shia is in a 12-step program. The rep says "he has taken the first of many necessary steps toward recovery."

We also got pics Tuesday showing Shia carrying an AA book for all to see.