The (bisvinyl)siloxane 2-methyl-1,4-naphthoquinone platinum complex 1 catalyzes the hydrosilylation of styrenes 2a-e with triethylsilane. The beta -silyl regioisomers are formed as major products along with minor amounts of ol-isomers and E-beta -silyl styrenes. Depending on the styrene substitution pattern, the turnover numbers range between 553 and 973. Trimethylvinylsilane undergoes regioselective beta -silylation in good yields. A 8:1 regiopreference in favor of the beta -silyl addition product is observed for 1-pentyne.