The main enemy in rice production is the attack of stinky bugs, brown planthoppers, grasshoppers, ladybugs, aphids, and others. This attack inhibits the growth of rice plants, thereby reducing production or even thwarting the harvest. Chemical pesticide application can reduce pests and diseases. However, the long-term use of chemical pesticides can disrupt the ecosystem. This study aims to study the application of plant-based pesticides to the presence of pests and predatory insects for rice plants. The research was begun with the preparation of citronella-based pesticide from citronella extract obtained by mixing citronella with water at a weight ratio of 2:1. The extract was mixed with water at a ratio of 1 liter for 50 ml of citronella extract. The application of the prepared pesticide was carried out by spraying 21-DAP (day after planting) rice plants at two plots sizing 400 m2 each. The types and numbers of pests and predatory insects were observed before every pesticide application. Spraying was repeated weekly for the following 4 weeks. Results showed a decrease of insects in experimental plots A and B after the application of pesticides. After the fourth application, only one type of insect (green grasshopper) was found in plot A, and no insect was found in plot B. However, four types of insects were found in the control plot. The application of citronella-based pesticides is also related to the decrease of predatory insects’ population.