An object of the present invention is to provide a material used for producing a sheet for sealing a solar cell which is excellent in mechanical strength, solar cell sealing property and transparency if the material is not cross-linked.The thermoplastic resin composition of the present invention for sealing a solar cell is characterized by comprising: (A) 0 to 70 parts by weight of a propylene-based polymer having a melting point of 100° C. or higher and (B) 30 to 100 parts by weight of a propylene-based copolymer satisfying the following requisite (b); (b): MFR (230° C., load: 2.16 kg) falls in a range of 0.01 to 100 g/10 minutes, and at least one of the following requisites (b-1) and (b-2) is satisfied; (b-1): an rr fraction is 60% or more and (b-2): a structural unit derived from propylene is contained in an amount of 55 to 90 mole %, and a structural unit derived from α-olefin having 2 to 20 carbon atoms (excluding propylene) is contained in an amount of 10 to 45 mole %; and an intrinsic viscosity [η] (dL/g) measured in decalin at 135° C. and MFR described above satisfy a specific relational equation.