Mango is an important fruit crop and affected by several insect pests and diseases. Among insects, bark eating caterpillar is a serious problem in Bihar and causes heavy losses. An investigation was conducted for incidence of this insect and its management. The study on incidence of bark eating caterpillar Indarbela quadrinotata Walker revealed that young orchards of mango were less prone to bark eating caterpillar infestation in comparison to old orchards. In management practices it was found that poorly managed young orchards of mango had only 20.40 per cent infestation in comparison to 90.05 per cent in old orchards. Among different management practices evaluated, cleaning the infected hole + plugging holes with cotton swab dipped in lambda cyhalothrin 5 EC @ 1ml/litre + plugging holes with mud showed maximum mortality (81.33% in 2019 and 82.68% in 2020) of bark eating caterpillar with highest yield (48.80 t/ha and 50.30 t/ha during 2019 and 2020, respectively) and increased yield over untreated control as 156.84 per cent and 171.89 per cent in 2019 and 2020, respectively.