"The public protector wrote to the minister last month requesting a meeting and the minister responded by saying that as the matter is a subject of an ongoing court process, she was not going to avail herself for a meeting with the public protector, spokeswoman Kgalalelo Masibi said.
"The public protector decided to subpoena the minister because attempts to persuade her to meet have been ignored by the minister."
In February, Madonsela released a report on Motsoeneng, while he was acting chief operations officer.
She found that his salary increased from R1.5 million to R2.4m in one year, that he had purged senior staff, and misrepresented his qualifications-- that he had passed matric - to the SABC.
At the time, Madonsela recommended that a new COO be appointed to the SABC within 90 days.
In early July, Muthambi announced Motsoeneng's appointment, saying the decision was taken following a recommendation by the SABC board. She said he was cleared of all wrongdoing by a legal firm before being appointed permanently.
At the time, the Democratic Alliance launched a high court bid to have the appointment set aside.
Muthambi has filed court papers opposing it.