Coenzyme Q10 (CoQ10) is essential for all cells, and deficiency has been implicated in cardiovascular disease. Plant phytosterols inhibit cholesterol absorption, and may thereby also reduce cardiovascular risk. This study compared the relative bioavailability of CoQ10 solubilized in low-dose soybean phytosterols (SterolQ10) with a generic CoQ10 solubilizate. In a randomized, cross-over design, 36 healthy males received a single 100 mg dose of CoQ10, as SterolQ10 or generic CoQ10, with a two-week washout between treatments. Plasma CoQ10 was analysed at baseline, and at 2, 4, 6, 8 and 10 h after supplement ingestion. Subjects were then administered either 100 mg/day of generic CoQ10 or SterolQ10 for 4 weeks. Fasting plasma CoQ10 levels were measured at baseline and following supplementation. The two preparations were bioequivalent in regard to the area under the curve (AUC0–10h) and maximum increase in concentration (Cmax), with geometric mean ratios of 0.89 (CI 0.81–0.98) and 0.88 (CI 0.80–0.96), respectively. Four-weeks of CoQ10 resulted in a comparable twofold increase in CoQ10 levels for both formulations (p < 0.001), which was similar between preparations (p = 0.74). The combined CoQ10 and phytosterol formulation, SterolQ10, showed bioequivalence to the generic CoQ10 following a single CoQ10 dose, and demonstrated comparable bioavailability following multiple dose administration. Copyright © 2012 John Wiley & Sons, Ltd.