The Roman Catholic Diocese of Penang is situated in the northern region of Malaysia covering 5 states, namely Penang, Perlis, Kedah, Perak and Kelantan. It was created in 25 February 1955 together with the Archdiocese of Kuala Lumpur.
The first catholic priests settled in Malacca in the 1511. College General was established in Ayuthia, Thailand in 1665. It was moved to Cambodia before finally settling in Penang on 1808. A seminary occupied a site in Pulau Tikus before moving to their present site in Tanjung Bungah on 1984. In 1786, Captain Francis Light and his men landed in Penang and decided to build a church there. They constructed a church and it was completed on August 1787. The church was blessed on the Feast Of The Assumption (15 August). That was the first church in Penang, named the Church of the Assumption. A few years, later, another priest settled in Penang and used the College General place as their church. This was the second church in Penang named Church of the Immaculate Conception. More churches were constructed.
In 1940s, the World War II affected Penang. Some churches were closed all the time except for Sunday Masses. After World War II, there was a need of setting up a diocese. On 25 February 1955, the Diocese Of Penang was set up together with the Archdiocese of Kuala Lumpur.
Bishop Francis Chan and Archbishop Dominic Vendargon were the first Malaysian bishops to be ordained. Bishop Francis Chan was the first bishop of Penang. In 1967, due to the demise of Bishop Francis Chan, Bishop Gregory Yong was appointed as the second bishop of Penang. In 1976, Penang hosted the Aggiornamento for all bishops and priests in West Malaysia. In 1977, he was appointed as Archbishop Of Singapore. Bishop Anthony Soter Fernandex was ordained and became the third bishop of the diocese. However in 1983, he was appointed as Archbishop of the Archdiocese in Kuala Lumpur. Bishop Antony Selvanayagam then became the fourth bishop of Penang in 1983, he was previously ordained in 1980 and was formerly the Auxiliary Bishop of Kuala Lumpur. He retired in the year of 2012.