Satyendra Prasanna Sinha received his primary education from his hometown. Subsequently received a scholarship from "Presidency College", Calcutta. He also received an invitation from the bar of London's "Link's Inn". After returning to India in 1886, Sinha established a successful legal practice in Calcutta. In 1903, Sinha became a permanent advocate of the Government of India, rejecting the claims of an English barrister in 1903. He was the first Indian to be appointed as Advocate-General of Bengal in 1905, a post confirmed in 1908. His legal practice in 1908 was so lucrative that accepting the government's invitation meant a cut in annual income of £ 10,000. Sinha's first inclination was to turn down the Viceroy's invitation, but Jinnah and Gokhale convinced him to accept the job. He became the first Indian to enter the Viceroy's Executive Council in 1909. On 1 January 1915, he was knighted in honor of the New Year. Sinha was elected President of the Indian National Congress in the Bombay session of the Congress in 1915.
In 1917, Sinha returned to England to work as an assistant to Edwin Samuel Montagu, Secretary of State. Satyendra Prasanna Sinha passed the "Government of India Act - 1919" in the "House of Lords" based on the Montague-Chelmsford resolutions to amend the "Indian Constitution". Later, he also served as a member of the Imperial War Cabinet and Conference with Ganga Singh, the Maharaja of Bikaner after the outbreak of World War I, and represented India at the 1919 Peace Conference in Europe. In the same year, he was made the Under-Secretary of the Parliamentary State for India and also emerged as the Baron Sinha of Raipur on the presidency of Bengal. He became the first Indian member of the British House of Lords, taking his seat in February 1919. He was instrumental in passing the Government of India Act, 1919 through the House of Lords. He returned to India in 1920 and was appointed the first governor of Bihar and Orissa provinces. He was the first Indian to hold this position under British rule. His tenure as governor did not last long and he held the post for 11 months on the grounds of poor health. In 1926, Sinha moved back to England and joined the Judicial Committee of the Privy Council in London.