Family (Noctuidae) numbers 300 in the Republic of Moldova now. However, the most important species from the economic point of view are those, which have a hidden way of life, such as Cotton bollworm (Helicoverpa armigera) (Hübner,1808). One of the solutions for ensuring food safety and improving the environment can also serve the implementation of methods for monitoring the pest’s development. The purpose of the investigations was to determine the possibilities of H. armigera seasonal monitoring in the agroclimatic conditions of the Republic of Moldova using light traps. Following the seasonal collection of the biological material, it was found that for two years a rather impressive number of imagos (about 3072 specimens) of the H. armigera flea were attracted to the light traps. Based on the obtained results, we mention that the population density of the given pest can deviate from year to year, depending on climatic factors. Thus, it was found that the highest population density of the flea H. armigera was recorded during the vegetation period of 2022 with a total number of about 2656 imagos, which was 86% higher than the number of individuals attracted by the traps with light in the year 2021. During the vegetation period of 2022, the maximum number (1670) of imago H. armigera, attracted to light traps, was recorded in the third decade of August. At the same time, it was demonstrated that during the same period of 2021, a total number of only 108 imagos were recorded, attracted to light traps. The analysis of the obtained results tells us that the population density of the flea H. armigera, in the corresponding period of 2021, was about 15 times lower compared to 2022 Thus, the results obtained during the vegetation periods of two years allowed us to find that with the help of light traps it is possible to monitor the development of the H. armigera flea population, and to assess the population density. At the same time, based on the data collected during these two years, it was found that the pest H. armigera develops in III generations. It was mentioned that the appearance of the first imagos in 2021 (unfavorable climatic conditions) took place starting from the first decade of June and the development of populations lasted until the second decade of September. The favorable climatic conditions of 2022 conditioned the flight of the first imagos of the H. armigera flea to be recorded about a month earlier - from the first decade of May and lasted until the second decade of October, also by one month more than in 2021. The obtained results allow us to conclude that light traps can be successfully applied as a methodological element for monitoring the development of the H. armigera flea population and assessing the population density in the agroclimatic conditions of the Republic of Moldova.