The growing demand for sustainable energy and the increasing challenges associated with organic waste management have intensified the interest in biogas technology as a viable renewable energy solution. This study evaluated the biogas production potential of cow dung and kitchen waste through anaerobic mono- and co-digestion under controlled mesophilic conditions in Jalingo, Taraba State, Nigeria. Fresh cow dung and household kitchen waste were collected, characterized for their physicochemical properties, and subjected to anaerobic digestion for 40 days. Three treatment systems were investigated: cow dung only, kitchen waste only, and a 1:1 co-digestion mixture of cow dung and kitchen waste. The key parameters analyzed included pH, total solids, volatile solids, carbon-to-nitrogen ratio, cumulative biogas yield, methane concentration, and digestion efficiency. Data were analyzed using descriptive statistics and one-way analysis of variance at a 5% significance level. The results revealed significant variations in digestion performance among the substrate treatments. The co-digestion system produced the highest cumulative biogas yield (257.4 L), followed by kitchen waste (188.6 L) and cow dung (145.8 L). The methane concentration was also the highest in the co-digestion treatment (67.2%), compared with 59.6% and 54.8% for kitchen waste and cow dung, respectively. Similarly, the reduction of volatile solids, which is used as an indicator of digestion efficiency, reached 58.8% in the co-digestion treatment, exceeding the values recorded for the mono-digestion systems. The ANOVA results confirmed that the differences in biogas yield, methane concentration, and digestion efficiency were statistically significant (p < 0.05). This study suggests that the co-digestion of cow dung and kitchen waste substantially enhances biogas production and methane recovery compared with mono-digestion. The findings demonstrate that these locally available organic wastes can serve as sustainable feedstocks for renewable energy generation, waste reduction, and environmental management. The study recommends the promotion of household- and community-scale biogas systems, supportive policy frameworks, and increased investment in WT technologies to advance sustainable energy development in Nigeria.