The aim of the present study was to investigate the effects of glucose fluctuation on neointimal proliferation after stent implantation by optical coherence tomography (OCT) in a diabetic/hypercholesterolemic (DM/HC) swine model. A total of 24 everolimus-eluting stents (EES) were implanted in the right coronary artery (RCA) of the animals using a 20% overstretch ratio. The 24 swines were divided into a DM-high glucose fluctuation (HGF) group (n = 8), DM low glucose fluctuation (LGF) group (n = 8), and a control group (n = 8). Percent diameter stenosis (%DS), late loss (LL), percent area stenosis (%AS), and neointimal thickness (NIT) were analyzed. The differences in neointimal characteristics and circulating oxidative stress and inflammation biomarkers were assessed and measured. At 28 days, the highest values of %DS, LL, %AS, and NIT were achieved in the HGF group followed by the LGF group (P < 0.05) and the control group (P < 0.05). The highest frequency of the heterogeneous pattern was in the HGF group followed by the LGF group (P < 0.05) and the control group (P < 0.05). This was also the case for the oxidative stress and inflammation biomarkers. DM might have a deleterious impact on neointimal proliferation after EES implantation in this DM/HC swine model. The extent of glucose fluctuation may be related to the degree of neointimal proliferation and this needs to be further confirmed by long-term follow-up and histology.