The invention relates to a posterior chamber type artificial crystal which is provided with the design of an optical part capable of improving the image quality with a highly convex rear surface. By adopting the design of highly convex surface for the optical part of the posterior chamber type artificial crystal, and by adopting the design of a high-order aspheric surface or additionally adopting the design of a composite ring curve, the distance between the rear surface of the artificial crystal optical part and a rear sac is shortened, the stability of the artificial crystal in the space position of the sac is improved, the advantage of the square edge effect on the optical part edge of the artificial crystal is enabled to be better presented, and the morbidity of PCO (posterior capsular opacification) is reduced after the artificial crystal is implanted; and since the front surface of the optical part is slightly flat, the loop of the artificial crystal (particularly the loop of one one-piece posterior chamber type artificial crystal) is enabled not to be tightly pressed onto the front surface of the optical part during folding process, the loop is more easily unfolded after being implanted into an eye, the situation of mutual adhesion between a support loop and the optical part cannot occur, and the imaging quality of the artificial crystal and/or the vision quality of an astigmia patient can be improved.