Wat Kalayanamit Woramahawihan was built during the reign of King Rama III by Chao Phraya Nikorn Bodin Mahin Maha Kalyanamitra (To), who donated his house and the surrounding land and had it constructed as a temple in 1825. King Nangklao (Rama III) subsequently renamed it Wat Kalayanamit and commissioned the construction of the royal chapel and the main Buddha statue, a large Buddha statue called Phra Phuttha Trairattanayok or Luang Pho To, with the intention of emulating the old capital, which had a large Buddha statue outside the city walls, such as Wat Phanan Choeng in Ayutthaya.

This temple has been part of the city of Thonburi for generations and was built during the reign of King Nangklao. Originally, in 1825, Chaophraya Nikhom Bodin (To Kalyanamitra) donated his house and acquired additional land to build a temple. He presented it to King Nangklao, Rama III, who named it Wat Kalayanamit. Later, he commissioned and donated both the Royal Vihara and the main Buddha statue for the Royal Vihara, Phra Phuttha Trairattanayok (Luang Pho To). This statue is especially revered by the Chinese. It is also known as Sam Po Hut Kong or Sam Po Kong. It is a stucco Buddha statue in the Mara Vijaya posture, measuring 5 wah 3 sok across the lap and 7 wah 2 sok 10 inches in height. It is located in the large Vihara in the center of the temple. Between the small vihara and the ordination hall in front of the royal vihara stands a newly built bell tower, housing the largest bell in Thailand. Inside the ordination hall, which is smaller than the vihara, is the Pa Lai Lai Buddha statue in the Palilai pose, commissioned and presented to King Rama III. It is considered the only temple in Thailand with a main Buddha statue in the Palilai pose. The interior features murals depicting the life of Buddha and the daily life of the townspeople during the reign of King Rama III. Also located there is the Phra Thammathian Theling Phra Kiat Hall, which houses the Tripitaka from the reign of King Rama IV.