No data are available on the presence and content of Coenzyme Q10 (CoQ10) in human follicular fluid and its role. To assess the presence and concentration of CoQ10 in human follicular fluid in relation to oocyte fertilization. CQ10 content was measured in follicular fluid obtained from 20 infertile women undergoing ovarian stimulation program for in vitro fertilization. CoQ10 levels were assayed by high-performance liquid chromatography system and normalized for follicular cholesterol and protein levels. Oocyte morphology and embryo grading were assessed. CoQ10/Protein levels resulted significantly in mature versus dysmorphic oocytes. Similarly, CoQ10/Cholesterol was significantly higher in grading I-II versus grading III-IV embryos. This study is the first demonstration of the presence of CoQ10 in the human follicular fluid. Although the biological and endocrine mechanism of CoQ10 in the follicular fluid and its correlation with oocyte and embryo development is unclear, a new step may be the administration of CoQ10 in infertile women to evaluate the biological and reproductive outcomes.