This study gives an analytical solution of wave interaction with a new-type pile–rock breakwater in the context of linear potential theory. The pile–rock breakwater consists of two rows of closely spaced piles and a rock core between them. The matched eigenfunction expansion method is used to obtain the analytical solution. The analytical solution is confirmed by other solutions for several limiting cases of the present structure. The solution is also validated by a multi-domain boundary element method solution. The reflection coefficient, the transmission coefficient and the energy loss coefficient of the pile–rock breakwater are examined. Their significance for practical engineering is discussed.