To provide a styrene resin composition excellent in a balance among chemical resistance, mechanical strengths and moldability.

This styrene resin composition which, in the form of a molding, satisfies the relationships: 0.8≤x 3.0 and 0≤y≤0.54 (wherein x (wt.%) is the content of a styrene polymer of a molecular weight of 2,000,000 or above, and y (wt.%) is the content of a styrene polymer of a molecular weight of 3,000,000 or above), has a content of a styrene polymer of a molecular weight of 50,000 or below is 3.0-12.0wt.% and which has a molecular weight or 200,000-350,000 and a weight-average molecular weight of 200,000-500,000 in a molecular weight distribution curve as determined by GPC.