Herein,　we　demonstrate　a　hydrothermal　route　to　the　one-pot　synthesis　of　polymeric　mesoporous　silica　microcubes　(P@MSMCs)　for　the　adsorption　of　heavy　metal　ions.　During　the　synthesis　of　P@MSMCs　from　column　silica　gel,　the　roles　and　combination　of　the　polymer　and　an　etchant　were　characterized.　Moreover,　the　porosity　of　P@MSMCs　was　tailored　by　adjusting　the　reaction　temperature　between　75　°C　and　200　°C.　The　characterization　through　UV,　FTIR,　FESEM,　XRD,　BET,　and　EDX　techniques　exhibited　that　P@MSMCs　have　a　well-ordered　mesoporous　structure　with　cubic　morphology.　The　P@MSMCs　had　a　diameter　of　2　μm,　with　an　average　pore　volume　and　pore　size　of　0.69　cm3　g-1　and　10.08　nm,　respectively.　The　results　indicated　that　the　P@MSMCs　have　excellent　adsorption　capacity　for　Ag(i),　Ti(iv),　and　Zn(ii)　due　to　the　formation　of　an　aggregated　complex.　These　aggregations　led　to　affordable　density　difference-based　separation　of　these　metal　ions　through　centrifugation,　filtration　or　simple　decantation.　The　removal　efficiencies　for　Ag(i),　Ti(iv),　and　Zn(ii)　were　observed　to　be　520,　720,　and　850　mg　g-1,　respectively.　The　kinetic　studies　demonstrated　that　the　adsorption　performance　fitted　well　to　the　pseudo-second-order　kinetic　model.　The　as-synthesized　P@MSMCs　were　stable　in　the　wide　pH　range　of　4-8.　Significantly,　the　recycling　or　reuse　results　displayed　effective　adsorption　performance　of　these　P@MSMCs　for　up　to　5　cycles.　The　adsorption　results　obtained　herein　will　promote　the　development　of　similar　strategies　for　the　removal　of　heavy　metal　ions　from　natural　water.　This　journal　is　©　The　Royal　Society　of　Chemistry.