The properties of the triplet excited state of [60]fullerene-containing cyclic sulphoxide have been investigated by time-resolved absorption spectroscopy. Transient absorption bands of [60]fullerene-containing cyclic sulphoxide showed two decay-components, which were attributed to triplet excited states of different spin multiplicity. The properties of photoexcited states of [60]fullerene-containing cyclic sulphoxide are also reported.