The objective of the present study was to develop a novel nanogel containing Beta vulgaris L. hydroalcoholic extract and assess its efficacy for treating testosterone-induced alopecia. Beta vulgaris L. leaf hydroalcoholic extract nanogel (BVEN) was prepared by ionic gelation method, incorporated in carbopol 934 gel. Optimization of particle size and entrapment efficiency as the responses was carried out by central composite design response surface methodology. Prepared nanoparticles were evaluated for entrapment efficiency, particle size, zeta potential, polydispersity index, Fourier transform infrared spectroscopy, transmission electron microscopy, and differential scanning calorimetry. Nanogel was evaluated for pH, colour, appearance and homogeneity, viscosity, spreadability, in vitro release study, and stability studies. Further, 2.5% and 5% BVEN were also evaluated for antialopecic activity in Swiss albino mice by using parameters as hair growth initiation, testosterone content, total protein, prostate weight measurement, hair follicular density, anagen/telogen ratio, and histopathological studies. The resulting nanoparticles had better entrapment efficiency with particle size of 274 nm, polydispersity index of 0.259, and zeta potential of +28.8. BVEN pH 6.5, drug content, i.e., quercetin 99.84 ± 1.30 % and stigmasterol 99.89 ± 1.52 % , spreadability 20.3 ± 0.5925 g cm / sec , and viscosity 110 × 10 5 cps were observed. Stability studies showed that nanogel was stable at 4 ° C ± 2 ° C / 60 % ± 5 % RH. It was found that 5% BVEN showed better antialopecic activity as compared to 2.5% BVEN.