In the title compound, C(23)H(17)NO(3)S, the thio-phene and isoxazole rings each have an envelope conformation with the spiro C atom linking them forming the flap of the envelope in each case. The dihedral angle between the mean planes of the benzothio-phene ring and isoxazole rings is 81.35 (7)°. In the crystal, an inter-molecular C-H⋯O hydrogen bond links the mol-ecules into a chain running parallel to the a axis.