Court records show Pamela Bach entered the plea Thursday in a Los Angeles court and was sentenced to 90 days. She will begin serving the sentence in May.
She received 60 days of jail time because she was on probation for a previous drunken driving case when she was arrested in November. Authorities found she had a blood alcohol level of 0.14, well above the legal limit of 0.08.
Attorney Jon Artz says Bach "wants to do the right thing" and move forward with her life.
Bach was married to Hasselhoff for 16 years until he filed for divorce in 2006. She appeared as a cafe owner in several episodes of Hasselhoff's series, "Baywatch."