<p>Agroforestry conserves biodiversity while providing various environmental and socioeconomic benefits, yet information on the link between plant diversity and environmental and socioeconomic factors is limited. This study examined how perennial plant species diversity and density related to socioeconomic and environmental variables under two selected agroforestry practices. The study was conducted in Tarmaber district of the central highlands of Ethiopia, using data from 122 plots across 64 households. The study used a linear mixed model to analyze the data. Fifty perennial plant species were identified, with 60% indigenous, 36% introduced, and the remaining 4% endemic. The mean values of Shannon diversity and richness in home gardens were 1.11±0.06 and 15.95±0.83, respectively, while in woodlots, these values were 0.05±0.009 and 12.44±0.38, respectively. The number of shrub individuals in home gardens was higher than that of trees, whereas the number of trees exceeded that of shrubs in woodlots. The linear mixed model revealed that household size, seedling access and soil fertility positively impacted species richness in home gardens, while education and age positively influenced in woodlots (<i>p &lt; 0.05</i>). Education positively influenced plant species diversity and density in both practices, while distance from market negatively affected stand density (<i>p &lt; 0.05</i>). Overall, both home gardens and woodlots contribute to biodiversity conservation, influenced by socioeconomic and environmental factors. The findings of this study can aid in the conservation of agroforestry by considering both socioeconomic and environmental factors.</p>