  We propose cosmological redshift-space distortion of correlation functions of
galaxies and quasars as a probe of both the density parameter $\Omega_0$ and
the cosmological constant $\lambda_0$. In particular, we show that
redshift-space distortion of quasar correlation functions at $z\sim2$ can in
principle set a constraint on the value of $\lambda_0$. This is in contrast to
the popular analysis of galaxy correlation functions in redshift space which
basically determines $\Omega_0^{0.6}/b$, where $b$ is the bias parameter, but
is insensitive to $\lambda_0$. For specific applications, we present
redshift-space distortion of correlation functions both in cold dark matter
models and in power-law correlation function models, and discuss the extent to
which one can discriminate between the different $\lambda_0$ models.
