The objective of this study was to demonstrate the technology of kharif onion production with the use of improved kharif onion variety Bhima Super during kharif seasons of the years 2020–2021 and 2022–2023 at farmer’s field of various locations under the guidance of Krishi Vigyan Kendra, Birauli, Samastipur, Bihar. The investigation included measures like yield and economic performance, technology gap, extension gap, frontline demonstration technology index, and respondent farmer’s degree of adoption of the demonstration. Over the course of the study’s two years, it was found that there was a 19.74% enhancement in bulb yield above local check and that the average B:C ratio under the demonstration plot was 3.98 which was higher than that of control plots 2.19. When enhanced quality seed was adopted, the extent of adoption increased to 47.12 percent. The study displays the technology index (22.64%), the average technical gap (81.22 q/ha), and the extension gap (62.98 q/ha). Current research highlights the potentiality of frontline demonstration for dissemination of technology at the grassroots level.