The potential of Centella asiatica (L.) Urb. extracts from three different accessions (Kediri, Kulon Progo, and Tawangmangu) as active ingredients in topical anti-aging serum preparations. This study is based on the increasing problem of premature aging due to free radicals from pollution and UV radiation, which can damage skin collagen. The Gotu kola plant is known to be rich in secondary metabolites, especially triterpenoids, which function as antioxidants and can stimulate collagen synthesis, making it an ideal candidate for anti-aging formulations. This study was conducted in three stages. The first stage of this study explored the potential of Centella asiatica extracts from three accessions (Kediri, Kulon Progo, Tawangmangu) as active ingredients in topical anti-aging serums to overcome premature aging triggered by free radicals. The results of the first stage study confirmed the superiority of the Tawangmangu accession through a complete phytochemical profile and the highest antioxidant activity (IC50 = 7.78 µg/mL) with an SPF value of 6.12. The results of the second phase of research developing gold nanoparticles using green synthesis, showed that the system without PVA polymer achieved optimal colloidal stability (-29.6 mV), with a spherical shape with a size of > 100 nm and UV protection efficiency per particle, confirmed by FTIR, SEM, and EDX characterizations that proved the chemical adsorption of triterpenoid compounds on the nanoparticle surface. The results of the third phase of research found that the 2% gold nanoparticle formula of gotu kola extract (FN2) produced the highest SPF (6.24–6.52), in vivo test results in mice showed minimal skin irritation (erythema and edema = 0.25), as well as a significant increase in antiaging parameters including connective tissue thickness (794.61 ± 55.48 µm), collagen density (75.84 ± 3.73 µm), and the number of fibroblasts (30.37), making the gold nanoparticle serum preparation of gotu kola extract an innovative and effective natural antiaging cosmetic formulation.