This study aimed to determine the flowering and yield response of chili peppers Capsicum annuum to spraying with Ceratophyllum plant extract at 0, 10, and 20 mL/L and chelated nano-zinc at 0, 1, or 2 g/L. The experiment was a factorialrandomized complete block design of three sprays in three replicates under greenhouse conditions. Ceratophyllum extract provided high efficiency in enhancing chili pepper flowering and crop yield compared to the control treatment. Ceratophyllum extract alone at a concentration of 20 mL/L significantly increased the total flower set and yield/plant compared to treatments at lower concentrations and the control. The best results were obtained when using a combination of Ceratophyllum plant extract at 20 mL/L and nano-zinc at 2 g/L, which gave the highest values in the number of flowers (45.77/plant), fruit set (83.44%), number of fruits/plant (73.13/plant), total yield (1789.8 ton/ha), the ascorbic acid content in fruit (277.51 mg/100 g FW), and zinc in fruit (3.39%), compared to the lowest values in controls where only distilled water was sprayed. The Ceratophyllum extract showed good nutritional properties and unique components and can be efficiently used to improve yield in chili pepper plants and possibly be included in fertilizer combinations.