L Mallikarjun Mansur was born on 31 December 1910 at Mansur, Karnataka.His father, Bheemaraayappa was village headman, a farmer by occupation was an ardent lover and patron of music. He had 4 brothers and 3 sisters. His elder brother Baswaraj owned a theatre troupe, thus at age 9 Mansur did a small role acted inplay. Spotting the talent in his son, Mallikarjun's father engaged him to a travelling Yakshagana (Kannada theatre) troupe. The owner of this troupe took a liking to the tender and melodious voice of Mallikarjun and encouraged him to sing different types of compositions. Hearing one such performance, he was picked up by Pundit Appaya Swamy under whom he had his initial training in Carnatic Music. Sometime later, he was introduced to Classical Hindustani Music under Nilkanth Bua Alurmath of Miraj who belonged to the Gwalior Gharana. The latter brought him to Ustad Alladiya Khan, the stalwart and the then patriarch of the Jaipur-Atrauli Gharana, in the late 1920s, who referred him to his elder son, Ustad Manji Khan. Following Manji Khan's untimely death, he came under the tutelage of Ustad Bhurji Khan, the younger son of Ustad Alladiya Khan. This grooming under the Khan Brothers had the most important influence on his singing.

Mallikarjun Mansur was well known for command over a large number of rare (aprachalit) ragas such as Shuddh Nat, Asa Jogiya, Hem Nat, Lachchhasakh, Khat, Shivmat Bhairav, Bihari, Sampoorna Malkauns, Lajawanti, Adambari Kedar and Bahaduri Todi, as well as his constant, mercurial improvisations in both melody and metre without ever losingthe emotional content of the song. Initially, his voice and style resembled that of Manji Khan and Narayanrao Vyas, but gradually he developed his own style of rendition.

He also remained music director with His Master's Voice (HMV) and later music advisor to All India Radio.

He got Padma Vibhushan in. 1992.

He died in 1992.