A novel nanocomposite including cellulose, chitosan and Ni/NiO was fabricated from barely wastes, shrimp wastes, and Calotropis procera, respectively. It was characterized by TEM, SEM, TGA, DTA, FT-IR, BET, EDAX, and elemental analysis. 5–25 nm of Ni/NiO were dispersed on chitosan and cellulose. The BET isotherms results showed that the Ni/NiO had a pore size of 11.3 nm with a BET area of 13.8 m2 g−1. While, Chit-Cell@Ni/NiO nano-biocomposite had a pore size of 16.087 nm with a BET area of 15.539 m2 g−1. Then, Chit-Cell@Ni/NiO bio-nanocomposite was applied to the photodegradation of ciprofloxacin under sunlight. About 92% of ciprofloxacin could be efficiently degraded within 20 min. Radical quenching experiments confirmed the contribution of active species was in descending order of h+>•OH > •O2− in the Chit-Cell@Ni/NiO system. The possible ciprofloxacin degradation pathway has been proposed according to the intermediates detected by LC-MS. Also, Chit-Cell@Ni/NiO showed high durability and stability after three-cycle ciprofloxacin degradation. In short, this study offers an efficient green methodology to decrease the number of antibiotics in the water system.