A photopolymer composition comprising a polymer matrix or a precursor thereof including a reaction product between (i) a (meth)acrylate-based (co)polymer in which a silane-based functional group is located in a branched chain and an equivalent weight of the silane-based functional group is 300 g/eq to 2000 g/eq, and (ii) a linear silane crosslinking agent; a photoreactive monomer; and a photoinitiator, a hologram recording medium using the same, an optical element using the hologram recording medium, and a holographic recording method. The photopolymer composition can more easily provide a photopolymer layer having improved durability against temperature and humidity while having a large refractive index modulation value.