  We constrain the scalar field dark energy model with an inverse power-law
potential, i.e., $V(\phi)\propto {\phi}^{-\alpha}$ ($\alpha>0$), from a set of
recent cosmological observations by compiling an updated sample of Hubble
parameter measurements including 30 independent data points. Our results show
that the constraining power of the updated sample of $H(z)$ data with the HST
prior on $H_0$ is stronger than those of the SCP Union2 and Union2.1
compilations. A recent sample of strong gravitational lensing systems is also
adopted to confine the model even though the results are not significant. A
joint analysis of the strong gravitational lensing data with the more
restrictive updated Hubble parameter measurements and the Type Ia supernovae
data from SCP Union2 indicates that the recent observations still can not
distinguish whether dark energy is a time-independent cosmological constant or
a time-varying dynamical component.
