This study investigates the physical properties of a range of dental resins containing up to 30% by weight of tetrahydrofurfuryl methacrylate (THFMA). The principal monomer was 2,2-bis-(4(2-hydroxy-3-methacryloyloxypropoxy)-phenyl)-propane (bis-GMA) or 1,6-bis-(methacryloxy-2-ethoxycarbony lamino)-2,4,4-trimethyl-hexane (UDMA). Heat-cured resins were tested for Young's modulus, flexural strength, refractive index, polymerization shrinkage and degree of conversion. The results indicated that THFMA has negligible effects on the mechanical properties of bis-GMA and UDMA and on the refractive index of UDMA, whilst the other measured properties present a strong relationship with the concentration of the additive. The dental relevance of the results is discussed and it is concluded that there is scope for further research on the use of THFMA as a comonomer in resin-based materials for dental applications.