本发明系关于聚有机金属硅氧烷，其包含由通式(1)：M1Ox/2表示之金属氧基单元(其中M1系周期表之第4A族或第5A族之原子，且“x”系M1之化合价)、由通式(2)：M2Oy/2表示之金属氧基单元(其中M2系周期表之第2A族或第2B族之原子，且“y”系M2之化合价)，及由通式(3)：R1aSiO(4-a)/2表示之有机硅氧烷单元(其中R1系烷基、烯基、苯基、芳烷基或氢原子，且“a”系满足：0＜a≦3之数值)；以及可固化聚合物组成物，其含有此聚有机金属硅氧烷，且系借由硅氢化反应固化从而形成具有高折射率、高可见光透射率且极佳耐热性及耐湿性之固化产物。

A polyorganometallosiloxane comprising a metalloxy unit represented by general formula (1): M1Ox/2 (where M1 is an atom of group 4A or group 5A of the periodic table, and ''x'' is the valency of M1), a metalloxy unit represented by general formula (2): M2Oy/2 (where M2 is an atom of group 2A or group 2B of the periodic table, and ''y'' is the valency of M2), and an organosiloxane unit represented by general formula (3): R1aSiO(4-a)/2 (where R1 is an alkyl group, an alkenyl group, a phenyl group, an aralkyl group, or a hydrogen atom, and ''a'' is a number satisfying: 0 < a ≤ 3), and a curable polymer composition which contains this polyorganometallosiloxane and is cured by a hydrosilylation reaction to form a cured product with a high refractive index, high visible light transmittance, and excellent heat resistance and moisture resistance.