Field studies were conducted during Kharif 2020 and Rabi 2020–2021 at Hasthinapuram village, Ariyalur district, Tamil Nadu, India, to study the seasonal occurrence of major insect pests of groundnut in relation to weather parameters. The predominant pests recorded were the groundnut leaf miner, Aproaerema modicella, tobacco leaf caterpillar, Spodoptera litura, leafhopper, Empoasca kerri, and aphid, Aphis craccivora. During Kharif 2020, peak incidence of A. modicella and S. litura were recorded during the 35th standard week with 67 and 60 larvae per 50 plants, respectively, whereas E. kerri and A. craccivora reached maximum populations of 130 and 170 individuals per 50 plants during the 40th and 44th standard weeks, respectively. During Rabi 2020–2021, peak populations of A. modicella, S. litura, E. kerri, and A. craccivora were observed during the 11th, 10th, 7th, and 4th standard weeks, respectively.