Resin composition for sealing light-emitting element, light source device, and method for producing light source device

Provided is a resin composition for producing a sealing member having excellent heat resistance and sealing properties. This resin composition for sealing a light-emitting element has at least one of the following two properties: (i) a polymer (P1) containing a structural unit (A) represented by formula (1) and a structural unit (B) having at least one functional group selected from the group consisting of a carbonyl group-containing group, a hydroxyl group, an epoxy group, an isocyanate group, and a cyano group; (ii) has a polymer (P2) containing a structural unit (A) and a polymer (P3) containing a structural unit (B). 本发明提供用于制作耐热性和密封性优异的密封构件的树脂组合物。在本发明的发光元件密封用树脂组合物中，以下两项中的至少1项成立：(i)具有聚合物(P1)，所述聚合物(P1)包含下述式(1)所示的结构单元(A)、以及具有选自含羰基的基团、羟基、环氧基、异氰酸酯基和氰基中的至少1种官能团的结构单元(B)；(ii)具有包含结构单元(A)的聚合物(P2)和包含结构单元(B)的聚合物(P3)。