We construct, in D=3,4,6 and 10 space-time dimensions, supersymmetric Lagrangians for free massless higher spin fields which belong to reducible representations of the Poincaré group. The fermionic part of these models consists of spinor-tensor fields which are totally symmetrical with respect to their tensor indices, while the bosonic part contains totally symmetric tensor fields as well as the simplest mixed-symmetry fields. A peculiar feature of these models is that they describe higher- and lower-spin supermultiplets in different dimensions in a uniform way.