Due to the political transformations of the 19th century and the civil wars, the monastery went into a process of decline. In 1822 its properties were put up for sale and the monks were expelled by the liberal somatenes, who were confronting the absolutists. Subsequently, the monastery was abandoned and, for two years, suffered fires and looting, although the jewelry treasures had been previously removed. In 1825, in the ominous decade of Ferdinand VII, the monks returned to try to restore order, repair the damage and recover some of what had been lost. However, the ongoing disputes between liberals and absolutists proved disastrous for many monastic enclaves in Catalonia. During the first Carlist war in 1833, itinerant troops occupied the monastery; they violated the tombs, burning the robes in search of gold and precious stones. Later, numerous volumes and documents were recovered, and the remains of the tombs were transferred to Tarragona for safekeeping. Faced with the situation, both the young friars and the veterans decided to abandon the cloister, taking refuge in private homes and extracting the most valuable objects they could move, which caused the almost total loss of these goods. The library, archives and royal tombs were left in the monastery, exposed to future looting and desecration.

Looting, fires and lack of care had turned the complex into a set of forgotten ruins. In 1930 the Patronato de Poblet was created to rescue the ancient stones and works of art that were still preserved, and a Brotherhood of Friends of the Monastery was founded. These initiatives made it possible to recover a large part of the building, and in 1940 a group of four Italian Cistercian monks returned to the site.

Today, the monastery is still occupied by Cistercian monks, who look after the grounds, pray and maintain a small vegetable garden. In addition, they run a guesthouse that offers lodging to twelve men seeking a spiritual retreat, receiving voluntary alms in exchange, a common practice in many Spanish monasteries.