  In the past several decades, the standard cosmological model has been
established and its parameters have been measured to a high precision, while
there are still many of the fundamental questions in cosmology; such as the
physics in the very early Universe, the origin of the cosmic acceleration and
the nature of the dark matter. The future world's largest radio telescope,
Square Kilometre Array (SKA), will be able to open the new frontier of
cosmology and will be one of the most powerful tools for cosmology in the next
decade. The cosmological surveys conducted by the SKA would have the potential
not only to answer these fundamental questions but also deliver the precision
cosmology. In this article we briefly review the role of the SKA from the view
point of the modern cosmology. The cosmology science led by the SKA-Japan
Consortium (SKA-JP) Cosmology Science Working Group is also discussed.
