<p>The objective of this research was to determine the genetic parameters of the test day milk yield and milk constituents (fat, Solid-not-fat, total solid, protein, and lactose) in Bhadawari buffaloes maintained at the ICAR-Indian Grassland and Fodder Research Institute in Jhansi, Uttar Pradesh, India. Data on 2593 lactation records from 93 Bhadawari buffaloes, descended from 16 sires and 43 females were analyzed which covered a period of eight-years (2014 to 2021). In estimating the genetic parameters of all the traits under consideration, the Bayesian approach and Restricted Maximum Likelihood method were employed. The heritability estimates for test day milk yield (MY), fat (F), solid-not-fat (SNF), total solids (TS), protein (P), and lactose percentage of milk ranged between 0.05–0.06, 0.09–0.11, 0.12–0.13, 0.12–0.14, 0.01–0.08 and 0.06–0.07, respectively. For MY (0.05–0.06), F (0.12), SNF (0.08–0.09), TS (0.13), P (0.03–0.18), and lactose (0.06) in both approaches, a low proportion of variations linked to the permanent environmental effect (c² effect) of animals were detected. Repeatability measures for all the traits under study were low to moderate in nature, which ranged from 0.10 to 0.27. The genetic and phenotypic correlations between various traits analyzed exhibited a vast range of magnitudes where a low to high positive genetic correlations were observed for all except between milk yield and fat as well as milk yield and TS. The phenotypic correlations were also positive but low for all the traits under consideration except for milk yield with fat, SNF and TS.</p>