Was born the son of Varyam Singh and Nand Kaur at the village of Thikrivala, now in Sangrur district of the Punjab, in January 1890. An attack of smallpox when he was barely two years old left him totally blind. Yet he educated himself, first receiving instruction at the hands of two Sikh schoolmen, Sant Javala Das and Sant Bhola Singh, and then attending for nearly five years an institute for the blind children at Daudhar. He gained good command of Sikh theology and scriptures and came to be known as a Giani. Early in his life he took to preaching. The first centre he chose was Peshawar where he remained from 1911 to 1915, thereafter shifting to Rawalpindi, his host in that town being Nanak Singh, then a rising poet, who later became famous as a Punjabi novelist. From Rawalpindi, Giani Sher Singh started a series of Punjabi tracts and books, Gurmat Parchar Lari, to which he contributed the lives of Guru Hargobind, Guru Har Rai, Guru Har Krishan and Guru Gobind Singh. The Nitnem Satik, Guru Sahib to Ved, Guru Granth to Panth and Ragmala Darpan are some of his other betterknown works.

Transferring himself to Amritsar, he edited successively the Pardesi Khalsa, the daily Qaumi Dard, Asli Qaumi Dard, the Sikh Sevak and the Khalssa Sevak. His last newspaper was the weekly Punjab which he launched in 1938, after severing connection with the Khalsa Sevak. As a newspaper editor, Giani Sher Singh enjoyed great influence. His editorials were marked by forthrightness, a flair for polemics and argument and remarkable political acumen, and he was known for his strong advocacy of Sikh rights and interests. Besides his journalism, Giani Sher Singh also took active part in politics. He made powerful speeches from the Congress platform and was taken into custody for one of these and confined in jail from 23 June 1922 to 30 June 1923.

He was again arrested in October 1923 when the Shiromani Gurdwara Parbandhak Committee of which he was a member was declared to be an unlawful organization. He was released from Lahore Fort towards the end of January 1926 along with 19 other Akaf leaders who agreed to give an undertaking to work by the newly passed Sikh Gurdwaras Act. The other section of the Akalis, led by Teja Singh Samundri and Master Tara Singh, refused to give any such undertaking and continued in confinement. This was the beginning of a schism in the Akali ranks which resulted in the formation of two separate parties - Shiromani Akali Dal and the Central Akali Dal. Giani Sher Singh was a leading figure in the latter. Giani Sher Singh served another term in jail from 16 November 1931 to 17 May 1932 for participation in the Akali morcha at Daska.

In the first elections held under the Sikh Gurdwaras Act in the summer of 1926, Giani Sher singh was elected unopposed to the Shiromani Gurdwara Parbandhak Committee. In the committee his role was that of the leader of the opposition who for many a long year gave the ruling party led by Master Tara Singh a stubborn fight. Giani Sher Singh, who was vice-president of the Central Sikh League, represented the Sikhs in All-India forums such as the All Parties Conference held at Lucknow in August 1928 and the Unity Conference convened by Madan Mohan Malaviya and Shaukat Ali at Allahabad in November 1932. In the elections to the provincial assemblies held in the winter of 1936-37 under the Government of India Act of 1935, Giani Sher Singh lent powerful support to the Khalsa National Party sponsored by Sir Sundar Singh Majithia and Sir Jogendra Singh and played a crucial role in bridging the gap between the elitist group and the masses.

The Khalsa National Party won more than half of the Sikh seats against the Akali-Congress alliance and its representative Sundar Singh Majithia joined the ministry formed by Muslim-dominated Unionist Party. The wrangling between Master Tara Singh's Shiromani Akali Dal and Giani Sher Singh's Central Akali Dal continued until the two leaders decided to bury the hatchet, formally arriving at a compromise on 15 November 1941. Together they campaigned for Azad Punjab, a formula for readjusting the boundaries of the Punjab aiming at subtracting the Hindu-Sikh majority areas from the Muslim League's scheme of Pakistan.

Giani Sher Singh died on 7 October 1944 in the Civil Hospital at Amritsar where he had been under treatment for a tumour in the brain.