The Convent of San Pablo is the seat and religious house of the Order of the Dominicans or Preachers, founded by Saint Dominic de Guzmán in the 13th century, although the convent church that has survived to the present day was erected later, between the 14th and 16th centuries, in the late Gothic style.

Thus, the old convent is still linked to the Dominicans, who have their residence in a modern annexe, while the church is regularly worshipped as a parish church. The convent, dedicated to the Apostle Saint Paul, was founded by the saint from Burgos with episcopal support in 1219 or 1220, shortly before his death in 1221; it is therefore among the oldest of the Order of Preachers. Between 1184 and 1198 Domingo de Guzmán had been a student and professor at the University of Palencia, and his house, demolished in 1892, stood in the Plaza de San Pablo. In the same 13th century, the Dominicans Gil de Santarem and Pedro González Telmo, among others, took the habit and developed their religious life in this convent.

In addition, this temple was the site of the Cortes Generales de Castilla on three occasions: in 1296 the Queen Regent Maria de Molina convened them to guarantee the throne in favour of her son, Ferdinand IV, and in 1313. The General Chapter of the Order of Preachers was also held here. San Pablo enjoyed the protection of monarchs such as Sancho III, Sancho IV and Alfonso XI, who turned the convent into a royal residence and oratory, and it even received papal privileges from the pontiffs Gregory IX and Alexander III.

Construction work on the new church began in the 14th century and was not completed until the 16th century. In 1514, under the patronage of the Rojas family, Marquises of Poza and Lords of Monzón, who wished to be buried here, the original main chapel was demolished to build the current one, which was completed in 1534. The church was consecrated on 7 April of that year.

The church was occupied by French troops during the Spanish War of Independence, who used it as a military hospital and prison. Subsequently, in 1835, the Desamortización (confiscation) took it into the hands of the State, losing part of its former splendour. The Dominican community returned in 1844. In 1957, the Dominicans occupied a building annexed to the church, designed by Jacobo Romero in 1920, which until that year housed the courts and the Provincial Court of Palencia, and was then used as a residence and novitiate for the order.

The church was declared a National Historic-Artistic Monument by decree on 3 June 1931. It is also an Asset of Cultural Interest.

It is a church with three naves, the central nave being the highest, separated by compound pillars, with side chapels in the nave of the Epistle. The longitudinal axis in the central nave is 72.15 m long. The two side naves are finished off at the chancel with square apse chapels, which are precisely the only remains of the primitive 13th century church, while the central nave is closed off by an apse that is highly developed in height and width, serving as the main chapel. The vaults are ribbed with cambered vaults in the central nave, simple ribbed vaults in the side naves, and star-shaped vaults in the main chapel.