Polycystic Ovary Syndrome (PCOS) is a multifactorial reproductive, endocrine and metabolic disturbance which is very commonly observed in females of reproductive age group. The disease is still incurable however the use of synthetic drugs in combination with lifestyle is recommended. Accordingly, the present study was conducted to investigate the possible beneficial effects of sitagliptin on PCOS induced rats on control diet (CD)/high fat- high fructose diet (HFFD). PCOS was induced by giving testosterone propionate (TP) for 28 days to both the CD/HFFD rats and treated with STG i.p. for last 15 days. At the end of the experiment lipid profile, inflammatory markers, expression of NF-κB-p65, miR-24 and miR-29a, fibrotic and apoptotic proteins from ovary tissue were examined. Moreover, lipid accumulation and fibrosis of ovary tissue was further confirmed using Sudan III and Masson’s trichrome stain. STG treated rats exerted a significant decrease in levels of cholesterol, TG, LDL-C, VLDL-C, IL-6 and TNF-α and increased HDL-C level, miR-24 and miR-29a expression. STG treated groups expressed significantly decreased expression of NF-κB-p65, TGF-β1, p-Smad 2 and p-Smad 3 followed by no significant changes in the expression of BAX, caspase-9, caspase-3 and Bcl-2 in all the PCOS induced groups. Among all the CD/ HFFD fed groups, rats on HFFD showed more devastating effect which suggests that diet plays a major role in genesis of PCOS. In conclusion, current results reflect the potential impact of STG against dyslipidaemia, inflammation and fibrosis in PCOS rats via regulating dyslipidaemia and fibrosis via DPP 4 mediated miR-29a expression.