Background The objective of this study was to investigate proliferator-activated receptor (PPAR&#947;), fatty acid synthase (FAS) and hormone-sensitive lipase (HSL) mRNA and protein expression in fat tails of Tan sheep. Rams from different developmental stages (aged 3, 6, 9, 12, 15 and 18 months) were selected, and their tail measurements including length (L), width (W) and girth (G) were recorded. The mRNA and protein expressions of PPAR&#947;, FAS and HSL were examined by quantitative real-time polymerase chain reaction (PCR) and Western blot. Results The tail measurements increased with age. We observed no significant differences (P &gt; 0.05) of PPAR&#947; mRNA expression between ages 9 and 15 months, and between 12 and 15 months; FAS mRNA expression levels at each developmental stage were observed significantly in Tan sheep (P < 0.05); HSL mRNA expression with no significant differences were only observed between 6 and 15 months (P &gt; 0.05). Significant differences (P < 0.05) of PPAR&#947;, FAS and HSL protein expressions at each developmental stage were observed in Tan sheep. Conclusion We observed that the mRNA expression patterns of PPAR&#947; and FAS decreased first before they increased again and then this process repeated. Conversely, the mRNA expression patterns of HSL increased first before they decreased and then this process repeated. The protein expression patterns of PPAR&#947; and FAS decreased first before they increased again and then this process repeated. Conversely, the protein expression pattern of HSL increased first before it decreased again and then increased again.