  In this paper, we define and study subspace-diskcyclic operators. We show
that subspace-diskcyclicity does not imply to diskcyclicity. We establish a
subspace-diskcyclic criterion and use it to find a subspace-diskcyclic operator
that is not subspace-hypercyclic for any subspaces. Also, we show that the
inverse of invertible subspace-diskcyclic operators do not need to be
subspace-diskcyclic for any subspaces. Finally, we prove that every
finite-dimensional separable Hilbert space over the complex field supports a
subspace-diskcyclic operator.
