Efficient solar energy capture is crucial for boosting photosynthesis, but excess energy can lead to photodamage. Here, we developed a glycosylated antenna molecule TPyGal (4-(4-(2,2-bis(4-methoxyphenyl)-1-phenylvinyl)styryl)-1-(2-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)ethyl)pyridin-1-ium bromide) featuring a robust electron donor-acceptor structure and aggregation-induced emission property, for in vivo spectral recomposition of solar energy to optimize photosynthesis. TPyGal demonstrated strong assembly with the cell membrane of photosynthetic algae and exhibited low biotoxicity. As a biocompatible membrane antenna, TPyGal efficiently redistributed ultraviolet and blue light into red light on the algal cell membrane. Such intracellular spectral recomposition could reduce energy waste and mitigate photodamage, which significantly improved light utilization. Consequently, algae assembled with TPyGal showed a substantial increase in photosynthetic rates and biomass production. Furthermore, TPyGal acted as both a fertilizer and an artificial antenna, effectively promoting the photosynthesis and growth of higher plants, such as mung bean sprouts. This work provides a promising strategy for efficient solar energy conversion and photosynthesis enhancement.