Katt Williams Put on D-Fence by Construction Co.

Katt Williams may have seriously fenced himself in this time -- and it's all over a pile of cash he allegedly owes a construction company.

Extreme Fence Co. filed a lien against the comedian last month, claiming they installed an electric motorized gate and 106 feet of wrought iron fence at his Calabasas, CA home back in October ... but never got paid for the job.

EFC claims the bill came to $8,900 -- and now they want their money, stat.

Katt's reps did not return e-mails.