A successful application of the template displacement synthesis to the polymer templated mesoporous silica SBA-15 resulted in the preparation of materials with high surface area and open porosity. It was shown for the first time that such procedure is applicable for neutral polymer templated silica-based materials. Some of the materials, particularly the sample with attached 1-allyl-3-propylthiourea functionality, exhibited promising properties towards mercury ion adsorption. The maximum mercury loading from aqueous solution is 0.16 g Hg2+/g or 0.8 mmol Hg2+/g. The mercury desorption was accomplished by washing the mercury-loaded samples with aqueous thiourea solution.