Seborrheic dermatitis (SD) is the most common superficial fungal skin infection affecting large number of the population worldwide. Prevalence of this disease has been increased. The present study aimed to formulate topical gel loaded with Ketoconazole (KTZ) as an antifungal agent and black seed oil with anti-inflammatory or antifungal activity to effectively treat seborrheic dermatitis (SD). The dispersion method was used to formulate gel preparations using gelling agents (Carbopol 934, Methylcellulose, and Xanthan gum). The prepared gels were evaluated for organoleptic properties, pH, spreadability, rheology, and drug content. The antifungal assay was performed using Malassezia furfur. In vitro permeation studies were performed on Franz diffusion cells. For drug-excipients compatibility studies, FTIR was performed. According to ICH guidelines, three months of stability studies were performed. The results indicated that gel formulations follow non-Newtonian shear-thinning pseudo-plastic type flow; F2 has high drug content (92.22 ± 0.32%), and the zone of inhibition (22 ± 1.25 mm), and highest drug release (91.88 ± 0.11%). No physicochemical interactions were found between the drug and polymer. Stability studies revealed that the formulations were stable at 25 °C. In conclusion, a gel of KTZ with oil exhibited a synergetic effect and offered a potential SD treatment strategy, suggesting it may be an alternative treatment for SD.