This invention provides a pressure-sensitive adhesive composition that exhibits excellent pressure-sensitive adhesive properties after crosslinking treatment, does not cause lifting or lifting upon heat treatment or treatment under high-humidity conditions particularly even in the case of a pressure-sensitive adhesive layer having a reduced layer thickness, and has excellent durability. A pressure-sensitive adhesive layer formed using the pressure-sensitive adhesive composition, and a process for producing the same are also provided. Further, an optical member with pressure-sensitive adhesive comprising the pressure-sensitive adhesive layer and an image display using the same are provided. The pressure-sensitive adhesive composition is characterized by comprising 100 parts by weight of an (meth)acrylic polymer and 0.02 to 2 parts by weight of a peroxide, and 0.02 to 2 parts by weight of an isocyanate crosslinking agent, the (meth)acrylic polymer comprising as monomer units 50 to 98% by weight of an (meth)acrylic monomer represented by general formula CH2═C(R1)COOR2, wherein R1 represents hydrogen or a methyl group and R2 represents an alkyl group having 2 to 14 carbon atoms, and 0.1 to 35% by weight of a nitrogen-containing monomer.