The presiding deity in the temple is Lord Shiva in the form of Shiva Lingam. The presiding deity is locally popular as Rajanna who is accompanied by the idols of Sri Raja Rajeswari Devi and Siddi Vinayaka. It houses other temples dedicated to deities including Anantha Padmanabha Swamy, Bhimeshwara Swamy, Kodanda Rama and Kasi Visweswara. Hence Vemulavada temple is also called as 'Hari Hara Kshetram'.
Located on the banks of Mulavagu stream, Vemulawada was once the capital city of Vemulawada Chalukyas dynasty. It is said that Sri Raja Rajeshwara Swamy Temple was built during 750 to 973AD by Raja Narendra grandson of Parikshit. Tradition associate with this place with famous Telugu poet 'Bheemakavi'. The remains of the temples and sculptures show the great architecture of Chalukyas. There are several inscriptions available that refer the reign of Chalukyas. It was earlier known as Lemulavatika, Lembulavade, and finally transformed into Vemulawada.
Devotees carry out the unique ritual of 'Kode Mokku', the tying of ox and taking around the temple. The locals believe that Lord fulfills the wishes of devotees when devotees take the ox around the temple. After taking the cow around the temple, devotees hand over the cow to the temple committee.
Legend / Sthala Purana
Once upon a time a king named Sri Raja Raja Narendra came to this place to hunt wild animals. But accidentally he killed a Brahmin boy who was drinking water from a pond. Then he got an incurable disease and went on pilgrimage to many holy places and returned back to this place. One day he drank the Holy water from the Dharmagundam and slept the night praying the Lord Shiva. Lord Shiva appeared in King’s dreams and asked him to take out Lingam from Dharmagundam and place it in the temple.
Then the king took out the Lingam and cleaned it with Dharmagundam water. He has built a temple on the hill to keep Lingam inside the temple, while he was sleeping in the night ly Sidhas came and established the God’s idol inside the temple. When king was worried about missing the chance to establish Shiva Lingam, Lord Shiva appeared in his dreams and given a boon that king’s name will be associated with the place forever. Thereafter his incurable disease also got cured. Hence the god Shiva here is called Raja Rajeswara Swamy.