Intramammary administration of drugs for treatment of mastitis leads to direct delivery and high concentration of drugs at the site of infection. The present study was conducted to evaluate effect of extended intramammary antibiotic therapy on bacteriological cure in bovine clinical mastitis. A total of 144 infected quarters from 80 clinical cases of bovine mastitis were divided and treated with recommended (group A and group B) and extended therapeutic regimens (group C and group D) through intramammary administration of cefoperazone and cefuroxime, respectively. Bacteriological cure was assessed after five days of completion of therapy. Extended therapy using cefuroxime and cefoperazone for treatment of bovine clinical mastitis showed higher bacteriological cure as compared to recommended therapeutic regimen by approximately 10 and 17 per cent, respectively. The findings of the present study will be helpful for veterinary practitioners for selection of treatment regimens as an effort to improve the bacteriological cure in clinical cases of bovine mastitis.