Title: Structure of multiplicative tiling Abstract: Suppose Ω is a subset of the real line and A a discrete set of real numbers, both of mixed sign (else the problem is not really new), such that A.Ω is a multiplicative tiling of the real line. In other words almost every real number can be written uniquely as a product of an element of A and an element of Ω. When one tries to establish the structure of Ω (the tile) and A (the set of multiples), in analogy with known facts about additive tilings, some new phenomena arise and new problems need to be solved to achieve this goal. We show how these can be dealt with. A quick introduction to the structure of additive tilings is necessary and will be provided for free. Joint work with Yang Wang (Hong Kong).