Acute leukaemia (AL) is a heterogeneous neoplastic disease that occurs by the growth of abnormal lymphoid and myeloid cells in the bone marrow and blood leading to acute myeloid leukaemia (AML) and acute lymphocytic leukaemia (ALL). Conventional cytogenetics is a characteristic technique to hunch chromosomal abnormalities, it helps in the diagnosis and therapeutic approach of the disease by the molecular cytogenetics technique of fluorescence in situ hybridization (FISH). Chromosomal abnormalities in AL are performed by karyotyping to confirm specific chromosomal abnormalities using FISH. The descriptive study included 42 clinically diagnosed AL patients. Karyotyping analysis was performed using the standard Giemsa banding procedure. To confirm specific chromosomal abnormalities and all culture failure (CF) cases, FISH was done. Among 42 cases, 29 (69.4%) males and 13 (30.9%) females, AML comprised 22 (52.38%) cases, ALL 14 (33.33%) cases, and AL 6 (14.2%) cases. Normal karyotype was found in 18 (42.85%), abnormal karyotype in 16 (39.09%), and 8 (19.09%) were CF. Specific abnormalities of t(15;17), hyperdiploidy; t(3;3) with monosomy 7 in; del(9q22); del(2p); del(17p); del(Xq); 1~2 dmin; der(3); +11, +13 and composite karyotype. Hypodiploidy was strongly associated with AL, which signifies the loss of chromosomes causing potential risk. Composite karyotype, rare t(3;3) double minutes, +11,+13, del(9q), and del(Xq) were the novel findings reported in the South Canara region of Karnataka. Despite other molecular techniques, conventional cytogenetics remains the baseline in the diagnosis of malignancies.