  Cygnus X-1 is a well-studied persistent black hole X-ray binary. Recently,
the three parameters needed to estimate the black hole spin of this system,
namely the black hole mass $M$, the orbital inclination $i$ and the source
distance $D$, have been updated. In this work we redetermine the spin parameter
using the continuum-fitting technique for those updated parameter values. Based
on the assumption that the spin axis of the black hole is aligned with the
orbital plane, we fit the thermal disk component to a fully relativistic thin
accretion disk model. The error in the spin estimate arising from the combined
observational uncertainties is obtained via Monte Carlo (MC) simulations. We
demonstrate that, without considering the counteracting torque effect, the new
spin parameter is constrained to be a$_* > 0.9985$ (3$\sigma$), which confirms
that the spin of the black hole in Cygnus X-1 is extreme.
