Polyolefin compositions particularly suitable for cast film, exhibiting heat sealability, retortability, low haze and stiffness, comprising: 1) 75-85% of a propylene homopolymer or copolymer of propylene with ethylene and/or one or more C4-C10 α-olefin(s), the homopolymer or copolymer having melting temperature equal to or higher than 150° C., 2) 15-25% of a copolymer of ethylene with one or more C4-C10 α-olefin(s) containing from 20 to 30% of said C4-C10 α-olefin(s); said composition having MFR (at 230° C., 2.16 kg) of from 5-10 g/10 min, the total content of ethylene of from 10 to 20%, the total content of C4-C10 α-olefin(s) of from 2 to 8%, the ratio XStot/XSm of the total fraction soluble in Xylene at room temperature to the fraction soluble in Xylene at room temperature of the matrix component (1) of from 5 to 15, and the value of the intrinsic viscosity of the total fraction soluble in Xylene at room temperature (XSIVtot) of 1.5 dl/g or less.