The title compound, C 19 H 30 O 2 Si, has triclinic ( P ) symmetry at 100 K. The O atom of the epoxide group has a pseudoaxial orientation and the dihedral angle between the cyclo­hexyl and benzene rings is 85.80 (8)°. The C—O—Si—C t ( t = tert -but­yl) torsion angle is −177.40 (14)°. In the crystal, pairwise C—H⋯O links connect the mol­ecules into inversion dimers featuring R 2 2 (8) loops.