Organophosphorus compounds are widely used in synthetic chemistry, pharmaceuticals, agrochemicals, materials chemistry and other fields. The core of preparing organophosphorus compounds is the efficient and selective formation of C-P bond. Traditional methods for C-P bond construction including Michaelis−Arbusov reaction and nucleophilic substitutions of organometallic reagents (or metallic phosphorus) with toxic phosphorus halides (or organic halides). Transition-metal catalyzed C-P bond formation through cross-coupling reactions have also been developed in recent years. However, these methods have obvious disadvantages such as heavy pollution, low atom efficiency, harsh reaction condition and the requirement of metals. Herein, we report a novel strategy for the selective construction of C(sp³)−P(Ⅲ or Ⅴ) bond from >P(O)-H compounds and aldehydes. By using H₃PO₃/I₂ system, various secondary phosphine oxides could react with both aromatic and aliphatic aldehydes to afford valuable phosphines and phosphine oxides in good yields. This method features wide substrate scope, simple reaction conditions, and avoids the use of toxic halides and metals. To the best of our knowledge, this is the first example of forming C(sp³)−P(Ⅲ) bond from phosphorus(Ⅴ) compounds in one-pot without using metals.