Data are presented demonstrating room‐temperature operation of AlxGa1−xAs‐GaAs vertical‐cavity surface‐emitting lasers grown on Si substrates. The device structures are grown using molecular beam epitaxy and a grown‐in quarter‐wave AlAs‐GaAs stack is used as then‐side reflector and a nonalloyed Ag dot used as thep‐side reflector/contact. Pulsed threshold currents of ∼125 mA are obtained for a 15‐&mgr;m‐diam device.