To study the effects of growth regulator on flower regulation, yield and quality of guava cv. Hisar Safeda was carried out at Fruit Orchard Sarkaria Farm, Fatehpur Rajputan (Patiala) during the year 2019-20 and fruit analysis was undertaken in Post Graduate Laboratory, Department of Agriculture Science, Mata Gujri College, Sri Fatehgarh Sahib. The experiment was laid out in a Randomized Block Design (RBD) having nine treatments with three replications. Treatments consisted of NAA @ (300, 400 and 500 ppm), Ethrel @ (1000, 1500 and 2000 ppm), Urea (5% and 10%) and Manual Bud Removal (MBR), while the plants sprayed with water served as the control. Significant variations were recorded during investigation with different treatment of Ethrel, NAA and urea on vegetative growth, flowering, yield and quality of guava cv. Hisar Safeda. In rainy season, maximum fruit length, fruit breadth and fruit weight was recorded in treatment of Ethrel @2000 ppm. However, during winter season maximum fruit length, fruit breadth and fruit weight was recorded in Control (Water spray). Highest fruit firmness was recorded in fruits under control treatment (water spray) during both season of study. Treatment combination of Ethrel @2000 ppm showed maximum and significant increased in quality characteristics viz. TSS, ascorbic acid, total sugars, reducing sugars and non-reducing sugars.