A microbial fuel cell (MFC) using moss as a medium was studied, and a biophotovoltaic power generation system (BPV) for desktop continuous power generation was designed. The organic compounds produced by moss during photosynthesis enter soil containing symbiotic bacteria. The metabolic process of bacteria decomposing organic matter produces electroactive substances. Inserting electrodes in the soil can collect these electrons and generate voltage. By studying different soil types and humidity conditions, the voltage output of moss power generation devices under different conditions is compared to evaluate the optimal operating environment of moss power generation units. To improve the efficiency and output of moss-based power generation systems, multiple factors need to be considered, including soil type and humidity conditions. The ability of different types of soil to maintain nutrients, manage water, and support microbial activities varies significantly, which has a significant impact on system performance. The humidity conditions must be carefully adjusted because the moisture content not only affects the photosynthesis efficiency of moss, but also affects the metabolic process of bacteria. Low humidity can limit the growth and activity of moss and bacteria, while high humidity can lead to anaerobic environments, inhibit the activity of certain bacteria, or promote the growth of non-electric producing microorganisms.