Malwathu Maha Viharaya is the main temple of the Malwatta chapter of Siyam Nikaya. The monastery is one of the three guardians of the sacred tooth relic which resides in the Temple of the Tooth. It was believed that the Kandyan King Senasammatha Vickramabahu built the monastery in the late 15th century alone with a stupa and an ordination hall as the residence for three monks. However the monastery now is home for many Buddhist monks including members of the executive council of Malwatta chapter. King Kirti Sri Rajasinha of Kandy built an assembly hall used for meetings.
Originally the monastery consisted of three temples, Sangharaja Temple, Tibbotuwawe Temple, Poyamalu Viharaya. These temples still exist and houses valuable buddhist documents and books which were used by the first monks of the respective temples. There is an octagonal shaped library in the monastery that houses a lot of valuable books on buddhism.