This study was under taken to assess the ability of plant growth regulators (PGRs) to improve the fruit yield and quality in 'Mosambi' Sweet orange. Various concentrations of 2, 4-D dichlorophenoxy acetic acid (2, 4-D) (10, 20 and 30 mg/l), gibberellic acid (GA3) (10, 20 and 30 mg/l) and naphthalene acetic acid (NAA) (10, 20 and 30 mg/l) were applied at the time of mid bloom stage and 2nd and 3rd sprays at 2 weeks interval from mid bloom were sprayed during 2014-15 and 2015-16 years on 10 years old 'Mosambi' sweet orange plants grafted on rough lemon root stock. A Randomized complete block design was followed with three replications and two trees were assumed to be an experimental unit. The overall objective of the experiment was to increase the productivity and quality of 'Mosambi' sweet orange. Exogenous application of all the PGRs significantly increased the fruit set percentage (76.30 and 75.77 % with 10 mg/l GA3), number of fruits per tree, less peel thickness, lowest peel percentage and highest yield per tree was observed with 10 mg L-1 2, 4-D during the both years. Maximum average fruit weight, fruit length, fruit equatorial diameter, fruit volume and maximum juice (%) was noticed with 20 mg L-1 GA3, less number of seeds per fruit was observed with 20 mg L-1 GA3 during the both the years. More total soluble solids and maximum total sugars, reducing sugars, non-reducing sugars were observed with 10 mg L-1 NAA during the both years. Lowest acidity, maximum sugars to acid ratio, highest ascorbic acid content was noticed with 20 mg L-1 NAA during the both years. Benefit : cost ratio was highest with treatment T1 (10 mg L-1 2, 4-D) during the both years