Summary: We study holographic duals of type II and heterotic matrix string theories described by warped \(\mathrm{AdS}_3\) supergravities. By explicitly solving the linearized equations of motion around near horizon D-string geometries, we determine the spectrum of Kaluza-Klein primaries for type I, II supergravities on warped \(\mathrm{AdS}_3\times S^7\). The results match those coming from the dual two-dimensional gauge theories living on the D-string worldvolumes. We briefly discuss the connections with the \({\mathcal N}=(8,8),\;{\mathcal N}=(8,0)\) orbifold superconformal field theories to which type IIB/heterotic matrix strings flow in the infrared. In particular, we associate the dimension \((h,\overline h)=(3/2,3/2)\) twisted operator which brings the matrix string theories out from the conformal point \(({\mathbb R}^8)^N/S_N\) with the dilaton profile in the supergravity background. The familiar dictionary between masses and ‘scaling’ dimensions of field and operators is modified by the presence of non-trivial warp factors and running dilatons. These modifications are worked out for the general case of domain wall/QFT correspondences between supergravities on warped \(\mathrm{AdS}_{d+1}\times S^q\) geometries and super Yang-Mills theories with 16 supercharges.