The 74-year-old's most recent public appearance was at a ceremonial Constitutional Court session in honour of chief justice Arthur Chaskalson in February.
SA Law Society spokesperson Krish Govender wished Langa a quick recovery.
"I feel strongly for him and his family and hope that he will make a speedy recovery.
"Many people still rely on him for his skills and I hope he will continue to assist and support the people of South Africa after he recovers."
