A Riemannian manifold
$\left( M,\,\rho\right)$ is called Einstein if the metric
$\rho $ satisfies the condition
$\text{Ric}\left( \rho\right)\,=\,c\,\cdot \,\rho $ for some constant
$c$ . This paper is devoted to the investigation of
$G$ -invariant Einstein metrics, with additional symmetries, on some homogeneous spaces
$G/H$ of classical groups. As a consequence, we obtain new invariant Einstein metrics on some Stiefel manifolds
$SO\left( n \right)/SO\left( l \right)$ . Furthermore, we show that for any positive integer
$p$ there exists a Stiefel manifold
$SO\left( n \right)/SO\left( l \right)$ that admits at least
$p$
$SO\left( n \right)$ -invariant Einstein metrics.