  We study D-instanton solutions in type IIB supergravity on $AdS_5\times
T^{1,1}$, which has a dual ${\cal N}=1$ $SU(N)\times SU(N)$ super Yang-Mills
theory. Apart from ordinary D(-1)-brane instantons, we discuss wrapped
D1-branes over minimal 2-cycles and derive explicit solutions preserving half
the supersymmetries. These solutions are identified with Yang-Mills instantons
which are (anti)self-dual in both gauge group factors with instanton charge
$(k,k')$. By examining the boundary behaviour of the solutions we discuss the
coupling to the corresponding dual boundary operators, and identify their
vacuum expectation values. We also discuss the boundary terms and compute the
action for these solutions.
