The regulatory mechanism of leptin's afferent action in the brain is contingent upon the efferent sympathetic innervation of white and brown adipose tissues. Nonetheless, the peripheral regulation governing the afferent-efferent balance remains ambiguous. Here we show the enriched expression of both leptin receptor (Lepr) and β2-adrenergic receptor (Adrb2) in perineurial cells that form a barrier around sympathetic ganglia and nerve bundles in adipose tissues, using single-cell RNA sequencing on mouse sympathetic ganglia. Lepr+ sympathetic perineurial cells (SPCs) are molecularly similar to endothelial cells. Conditional knockout of Adrb2 in Lepr+ cells, including SPCs, predisposes male mice to obesity by lowering energy expenditure and thermogenesis without affecting food intake. Notably, obesity-associated hyperleptinaemia causes apoptosis in SPCs, disrupting the perineurial barrier and concomitant adipose sympathetic neuropathy. This deleterious effect can be reversed by partial reduction of leptin or sympathomimetic β2-adrenergic receptor agonism. Clinically, we observed a male-specific synergistic effect of LEPR and ADRB2 polymorphisms on increased body mass index risk in a large European population. We propose that SPCs coordinate the afferent and efferent arms of the neuroendocrine loop of leptin action to regulate energy expenditure and body weight.