Abstract: The present invention relates to a magnetic block toy, and more particularly, to a magnetic block toy which makes assembly of blocks firm because caps having serrated coupling parts are combined to both sides of a block body, and which has block bodies and caps of various colors, thereby arousing children's interest and promoting development of intelligence. The magnetic block toy according to the present invention includes: a block body having a pair of brackets each of which has a protrusion and a groove formed on the inner face to correspond to each other and are coupled with each other; caps which are respectively combined to both sides of the block body and each of which has a serrated coupling part formed on the outer surface; and a magnet which is disposed inside the cap to generate a magnetic force.