The studies were carried out during the year of May 2014 to May 2015 to estimate the correlation among some performance traits of Thari cattle. The recorded data which include three sires with 15 daughters from each sire and four lactations of each daughters were observed. The averaged birth weight and weaning of three sires daughters was found 17.7 + 1.75, 17.38 + 1.01, 17.4 + 1.92 and 43.18 + 2.07, 42.6 + 2.49, 42.7 + 4.19, respectively. The result showed that higher birth weight was observed in daughters of sire- B whereas the lowest birth weight was found in daughters of sire- C and the higher weaning weight was found in daughters of sire- A and lowest weaning weight was found in daughters of sire-B. The milk yield of 1st, 2nd, 3rd and 4th lactation yield of all daughter were found averaged 861.60±70.40, 1046.78 ± 62.36, 1200.91 ± 111.21 and 1070.87 ± 54.56 liters, respectively. The result showed that 3rd lactation yield was significantly (P<0.05) higher than 1st, 2nd and 4th. The sire wise birth weight, weaning, milk yield and lactation length showed a non-significant different. The results of simple correlation for birth weight x weaning weight and milk yield x lactation length were 0.478 and 0.548. The result of environmental correlation for birth weight x weaning weight and milk yield x lactation length were 0.05 and 0.91. The results of genetic correlation for birth weight x weaning weight and milk yield x lactation length were -0.008 and -0.67. The results of phenotypic correlation for birth weight x weaning weight and milk yield x lactation length were 0.06 and 0.24, respectively. Keywords: Genetic, Phenotypic, Environmental, correlation, Milk yield. Lactation Length, Birth weight, weaning weight
