7:41 PM PT -- A rep for Williams tells TMZ ... he filed the divorce docs in CA superior court, claiming irreconcilable differences.
Williams commented, "Despite best efforts to work things out or make allowances, and as difficult as it is, sometimes you have to do what's best for everyone."
Anson Williams -- famous for playing Potsie Weber on "Happy Days" -- apparently is no longer happy with his marriage ... because he just filed for divorce.
According to court records, Anson filed for divorce from his wife, Jackie Williams, Wednesday after 30 years of marriage. It's unclear what led to the split.
Anson and Jackie tied the knot back way back in 1988, and they have 5 children together.
It's the second divorce for Anson ... he was previously married to Lorrie Mahaffey for 8 years from 1978 to 1986, before breaking things off.
Anson rose to fame on "Happy Days" playing Potsie, the gullible singer ... and for his role he was nominated for the Golden Globe award for best supporting actor.
He later became a big time TV director, working on huge shows like "Melrose Place," "Beverly Hills, 90210," "Sabrina the Teenage Witch," and "Lizzie McGuire."
Originally Published -- 5:29 PM PT