His parents were originally from Nadipudi village, West Godavari District of Andhra Pradesh.

When Mahatma Gandhi gave a call for boycott of the law courts, educational institutions and legislative bodies, Kala Venkata Rao who was bubbling with patriotic enthusiasm responded to this call; gave up his studies and jumped into the fray.

Rao married Rajeswaramma, the daughter of Duvvuri Venkateswarulu, then the village munsiff of Mukkamala, on 20 April 1914.

He is related to Sripada Krishnamurty Sastry, the first poet laureate of Andhra Pradesh and Bouloussou Soubramanion Sastroulou, politician from French Yanam through their wives and Sripada Venkata Ratnamba (née Kala) and Bouloussou Souryapracassamma (née Kala), respectively.

He held cabinet ministries during tenures of Omandur Ramaswamy Reddiar and Kumaraswamy Raja.

However, he was runner-up from Amalapuram constituency in 1952 election, where he lost to Nadimpalli Ramabhadra Raju of KMPP.

The Speaker of the Lok Sabha, M. A. Ayyangar, while paying homage to Rao called him "one of the stalwart statesmen of Andhra Pradesh".