The　earthquake-induced　pressures　on　arrays　of　cylinders　have　received　less　concern,　although　pile　groups　have　been　widely　adopted　in　real　practice.　This　paper　develops　an　analytical　method　to　investigate　the　interaction　of　water　with　arrays　of　rigid　circular　cylinders　subjected　to　horizontal　ground　motion.　According　to　seabed　and　surface　boundary　conditions　and　using　the　variable　separation　method,　the　three-dimensional　governing　equation　of　water　is　first　transformed　to　a　two-dimensional　Helmholtz　equation　in　the　xy-plane　and　analytical　vertical　modes　in　z-direction.　Then,　the　analytical　solution　of　the　hydrodynamic　pressures　on　arrays　of　cylinders　is　deduced.　This　analytical　solution　includes　the　radiated　wave　pressures　generated　by　each　cylinder　due　to　the　ground　motion,　first-order　scattered　wave　pressures　due　to　the　radiated　waves,　and　high-order　scattered　wave　pressure　due　to　diffracted　waves.　The　finite-element　method　is　employed　to　validate　the　present　analytical　solution.　The　results　show　that　the　analytical　solution　agrees　well　with　the　numerical　solution.　The　proposed　method　is　finally　used　to　investigate　the　earthquake-induced　hydrodynamic　forces　on　linear　arrays　of　circular　cylinders.　(C)　2021　American　Society　of　Civil　Engineers.