GURMUKH SIṄGH GIĀNĪ, BHĀĪ (d. 1843), a man of letters and an influential courtier in Sikh times, was the son of the celebrated scholar, Bhāī Sant Siṅgh, who had been the custodian of Srī Darbār Sāhib at Amritsar. Gurmukh Siṅgh was trained in Sikh religious lore at Amritsar under the care of his father. When the father, saddened by the death of his younger brother, Gurdās Siṅgh, quit his office and retired to Amritsar to devote himself to reading and expounding the Scripture, Gurmukh Siṅgh succeeded to his position at the court. He took over his father's work at Srī Darbār Sāhib after the latter's death in 1832. His influence at the court however diminished during the time Prince Nau Nihāl Siṅgh held the reins of power.

         After the death of Mahārājā Khaṛak Siṅgh and Prince Nau Nihāl Siṅgh in November 1840, Bhāī Gurmukh Siṅgh took up the cause of Kaṅvar Sher Siṅgh. On the die being cast in favour of Rāṇī Chand Kaur, he was one of those who signed the document for her regency, but went over to Sher Siṅgh as soon as he arrived in Lahore in the second week of January 1841. On assuming the throne, Sher Siṅgh treated Bhāī Gurmukh Siṅgh with great consideration bestowing upon him liberal jāgīrs.

         Bhāī Gurmukh Siṅgh fell a prey to courtly intrigue soon after the death in September 1843 of Mahārājā Sher Siṅgh. Hīrā Siṅgh Ḍogrā who had gained power during the reign of minor Mahārājā Duleep Siṅgh had him seized and assassinated and confiscated his family jāgīrs. His sons were also taken into custody, placed in chains and treated with cruelty.