Provided is a synthetic vitreous material which is not toxic to the ocular tissue, is capable of maintaining an intraocular tamponade effect for a long term, and is excellent in handleability. A synthetic vitreous material of the present invention includes a self-assembling peptide and a salt, and has an osmotic pressure of 40 mOsm/kg to 200 mOsm/kg. The synthetic vitreous material of the present invention is not toxic to the ocular tissue, is capable of maintaining an intraocular tamponade effect for a long term, and is excellent in handleability.
