Temples
The Vadakkunnathan temple, believed to have been founded by the legendary saint Parasurama, is an example of the Kerala style of architecture and houses several sacred shrines and murals delineating graphically, various episodes from the Mahabharata. Thiruvambadi Sri Krishna Temple, one of the largest Sree Krishna temples in Kerala and Paramekkavu Bagavathi Temple which is one of the largest Bagavathi temples in Kerala is also situated in the city. Sree Guruvayurappan Temple, is located in Guruvayur (municipal town), Thrissur District. It is also referred to as Bhuloka Vaikunta which means "Holy Abode of Vishnu on Earth".The Thriprayar Sreerama temple and Irinjalakuda Kudalmanikyam temple which are part of naalamabalam is also in Thrissur.

Churches
Asia's tallest church, the Our Lady of Dolours Syro-Malabar Catholic Basilica (Puthan Pally), Our Lady of Lourdes Syro-Malabar Catholic Metropolitan Cathedral which has an underground shrine, is a masterpiece of architecture. Mart Mariam Cathedral, the oldest church in the city, which belongs to the Assyrian Church of the East also known as Chaldean Syrian Church of the East, is situated in Thrissur. The St. Anthony's Syro-Malabar Catholic Forane Church, also known as Chinna Roma (Small Rome), which is around 300 years old, are also in Thrissur.

Mosques
The Chettiyangadi Hanafi Mosque in Thrissur City is one of the oldest mosque in Thrissur. Kalathode Mosque (Kalathode Juma Masjid) in Thrissur city has the facility of cemetery. Kokkalai Juma Masjid, Westfort Sunni Juma Masjid (West Fort), Salafi Juma Masjid near Railway Station, MIC Juma Masjid near Shakthan Bus Stand, Ayyanthole Juma Masjid (Ayyanthole), Olari Juma Masjid(Olari) are other mosques in Thrissur City. Cheraman Juma Mosque in Kodungalloor, ( 40 km from Thrissur ) is the First Mosque in India.