The Briton is now searching for her fourth coach in less than a year.
Beltz was hired following Raducanu’s U.S Open victory last year.
“I want to thank Torben for his coaching, professionalism and dedication over last half a year,” said Raducanu in a statement. “He has a huge heart and I have enjoyed our strong chemistry during the time together.”
She added: “I feel the best direction for my development is to transition to a new training model with the LTA supporting in the interim.”
The 19-year-old highlighted her desire for a more experienced mentor, which had initially led to Beltz.
Raducanu continues her clay-court run in Madrid this week.