Abstract: Present account is a brief summary of the work done on the electron theory of catalysis as applied to phytosynthesis during the last ten years. It comprises: 1. analysing the errors of the theory of two photochemical systems in photosynthesis; 2. applying the electron theory of catalysis to the mechanism of photosynthesis; 3. giving the experimental proofs of the inference and 4. using semiconductors instead of chloroplasts to photoreduce NADP to NADPH; synthesis of ATP from ADP and inorganic phosphate under near ultraviolet light.