The Trinity Church in Kasimov is first mentioned in the land books of Prince Peter Voeykov in 1627. It was a wooden structure with an altar in honor of St. Nicholas the Wonderworker, which housed many ancient icons. These icons were richly decorated but were valued primarily for their miraculous properties. On September 27, 1751, permission was granted to build a new church to replace the old one, with altars dedicated to St. Seraphim and St. Nicholas. By December 18, 1752, the well-known merchant Ivan Stepanov requested the consecration of the altars in the newly built church.

On the porch of the Trinity Church, there is an inscription indicating that construction began on May 11, 1753, and the consecration took place on May 6, 1763. The second altar of St. Sergius of Radonezh was consecrated on May 7 of the same year, and the church of the Holy Trinity was consecrated on September 10, 1765. The inscription also states that the church was built through the efforts of merchants Alexander Grigorievich Polezhaev and Nikita Semyonovich Verein with the support of parishioners. It is important to note that merchants in the city actively participated in the construction of Orthodox churches, and parishioners of all classes donated funds for their decoration. In 1772, a stone bell tower was erected, in the second tier of which there was a church in honor of the Smolensk Icon of the Mother of God. Services were held there only once a year, on June 28. Among the ancient relics of the church was a Gospel from 1644, which, like many other valuables, was confiscated in 1922. On the Day of the Holy Spirit, a procession was organized from the cathedral to the church. The church was repeatedly improved and decorated at the expense of the parishioners. It had four altars: the main one in honor of the Holy Trinity, the right altar in honor of St. Nicholas the Wonderworker, the left in honor of St. Sergius of Radonezh, and in the middle tier of the bell tower, in honor of the Smolensk Icon of the Mother of God. The church was closed on September 29, 1938, and in 1954 it was leased to the Kasimov quarry management by the decision of the city executive committee.

Services in the church resumed on September 15, 2002, after its restoration. The altars are being restored in honor of the Smolensk Icon of the Mother of God, St. Nicholas the Wonderworker, and St. Sergius of Radonezh.

The church houses the relics of the confessor Sergius of Kasimov, whose memorial day is celebrated with a solemn service, marking the church's feast day.