  The Penrose process of an extremal braneworld black hole is studied. We
analyze the Penrose process by two massive spinning particles collide near the
horizon. By calculating the maximum energy extraction efficiency of this
process, it turns out that the maximal efficiency increases as the tilde charge
parameter $d$ of the braneworld blackhole decreases. Interestingly, for the
negative value of $d$, the efficiency can be even larger than the Kerr case.
