Rodney King -- No Jail After 2nd DUI Arrest

Rodney King just got a slap on the wrist for his DUI arrest last summer -- striking a plea deal in which he won't have to serve a single second behind bars ... despite the fact he has a prior DUI conviction on his record.

Rodney pled guilty today to reckless driving for the July 12, 2011 incident in Riverside County, CA ... and in exchange, prosecutors agreed to drop the DUI charge.

Law enforcement sources tell TMZ, Rodney's blood alcohol level was only .06 at the time of his arrest -- below the legal limit -- but marijuana was also found in his system.

King was sentenced to 20 days house arrest and 3 years summary probation. He is also required to attend a 9-month alcohol education program, and pay a $500 fine plus court costs.

King dodged a major bullet by avoiding the DUI conviction ... because he was convicted for DUI in California back in 2004 ... and in CA, 2 DUI convictions within 10 years means MANDATORY jail time.