  In this paper, we propose the quantum spin pumping in quantum spin systems
where an applied electric field ($E$) and magnetic field ($H$) cause a finite
spin gap to its critical ground state. When these systems are subject to
alternating electromangetic fields; $(E,H)=(\sin\frac{2\pi t}{T},\cos\frac{2\pi
t}{T})$ and travel along the {\it{loop}} $\Gamma_{\rm{loop}}$ which encloses
their critical ground state in this $E$-$H$ phase diagram, the locking
potential in the sine-Gordon model slides and changes its minimum. As a result,
the phase operator acquires $2\pi$ holonomy during one cycle along
$\Gamma_{\rm{loop}}$, which means that the quantized spin current has been
transported through the bulk systems during this adiabatic process. The
relevance to real systems such as Cu-benzoate and ${\rm{Yb}}_4{\rm{As}}_3$ is
also discussed.
