The Canossian School started as a boarding school, called Canossian School for the Deaf in 1956. It was situated at 1 Sallim Road. Before that, it was known as Fatimah House which housed children with varying special needs. Later, some of the children were channelled to the other institutions for their education as it was not ideal to cater to such varied needs under one roof.
In 1970, the school moved to Jalan Merbok catering to deaf girls. Within three years, the boarding school was closed, thereby allowing both boys and girls to be admitted to the school.
Despite the relocation, the school was still considered part of Canossa Convent Primary School in Sallim Road. Sr Margherita was Principal of both campuses of the school. In 1979, the Canossian School for the Deaf became independent. Sr Angela Garavaglia became the ﬁrst Principal with St Helen Fernandez as the Acting Principal.