Polyimide resin composition

A polyimide resin composition, comprising:

• a glass fiber;
• and
• a polyimide resin mixed with the glass fiber and comprising a repeating structural unit of formula (1) and a repeating structural unit of formula (2),
• wherein a content ratio of the repeating structural unit of the formula (1) with respect to the total of the repeating structural unit of the formula (1) and the repeating structural unit of the formula (2) is 25 mol % or more and less than 40 mol %, and the formula (1) and the formula (2) are
• where R1 is a divalent group of formula (R1-3), R2 is a divalent chain aliphatic group having from 8 to 10 carbon atoms, X1 and X2 are a tetravalent group of formula (X-5),
• wherein an amount of the glass fiber mixed in the polyimide resin composition is in a range of 30 to 65 mass % relative to a total mass of the polyimide resin composition,
• wherein an average fiber length of the glass fiber is 3 to 6 mm, and
• wherein the glass fiber is surface-treated with at least one selected from the group consisting of a urethane-based sizing agent and a urethane/epoxy-based sizing agent.