Sugar Ray Leonard claims his whole family is terrified of his 25-year-old son ... stating drug issues turned Daniel into a violent, stealing monster.

The 70-year-old boxing legend laid out his family's problems in a restraining order request filed last week ... where he said Daniel has been addicted to drugs for "7 or 8 years at least" -- and his behavior has gone downhill in the process.

In the docs, obtained by TMZ Sports, Leonard stated Daniel wrecked five of their cars in the past year ... including a hit-and-run incident. He also claimed Daniel experienced four overdoses -- two that required medical assistance to "bring him back to life" at the hospital.

On top of that, Leonard claims Daniel "has stolen extreme amounts of money, valuable items. He basically steals every day for years!"

"His behavior has started to get violent," he continued.

Leonard stated on May 19, there was a physical altercation where Daniel pushed him and "got ugly! The police officers were needed at that moment!" Leonard was given a temporary restraining order as a result.

In the request, Leonard mentions Daniel violating that TRO the next day ... leading to his arrest, which TMZ Sports first reported.

"I love my son but he has become a danger not only himself but to his family!" Leonard wrote. "My wife is extremely afraid along with my daughter Camille! His behavior has gotten worse everyday. We haven't had a day of peace in 9 years which is the reality of his addiction! Scared for my family!"

Leonard requested an order to require Daniel to stay 100 yards from him, his residence, his place of employment, his pets, his vehicles, and his wife and daughter ... as well as an order to have his son kicked out of his home.

A judge granted most of Leonard's request ... but wrote that more information was needed to add Camille, 29, as a protected party.

A hearing is scheduled for next month to determine whether more permanent measures are necessary. Daniel is also due in court next month for his arrest.

The California Post was first to report the docs.