The method for cleaning sand which contains toxic and hazardous substances consists of the following steps: a) Sieving the contaminated sand with the sieve (3), b) Cleaning/scrubbing the contaminated sand in the attrition machine (4) in the slurry with adding of water from the water tank (5) for the purpose of removing toxic and dangerous substances as well as grease from the surface of the grains of sand, c) Grading/dripping on the dehydrator (8), in which cleaned sand and sludge are obtained, d) Sedimentation of sludge in the conical vessel (14) and removal of sludge by filtration, e) Separation of cleaned sand by grain size by using gravity concentration at the slurry separator (9 and 9') and concentration tables ( 10 and 10') where cleaned sand and wate-rock are obtained, f) Drying of cleaned sand, grading by grain size and storage and packing of sand graded in such manner, water, calcium oxide and aqueous solution of disodium metasilicate, sodium carbonate, benzalkonium chloride and ionic and/or non-ionic surfactants are added in the step b) of the sand cleaning process, which, when mixed within the attrition machine (4) create a mixture for the cleaning of sand and in the step d) filter press (17) is used for making an inert sludge cake.