A field experiment was conducted in a plastic greenhouse at the Department of Plant Protection, College of Agricultural Engineering Sciences, University of Baghdad (Al-Jadriya) during the 2025–2026 growing season to investigate the seasonal population dynamics of the tomato leaf miner, Tuta absoluta (Meyrick), and to evaluate the effectiveness of selected integrated pest management (IPM) treatments. The experiment was arranged in a randomized complete block design (RCBD) with three replicates. Sampling was initiated two weeks after transplanting and continued at weekly intervals until mid-March 2026. Leaf samples were collected from three canopy levels and examined to record different developmental stages (eggs, larvae, and pupae), and population density was expressed as individuals per leaf. Temperature and relative humidity were recorded and analyzed in relation to pest density using correlation and regression analysis. The tested control treatments included pheromone traps (Delta traps) baited with (E3, Z8, Z11)-tetradecatrienyl acetate, Spinosad 24% SC, and neem extract (Azadirachta indica), applied individually and within an integrated program. The results showed significant seasonal fluctuations in pest population, with peak densities occurring under moderate temperature and high relative humidity conditions. The IPM program achieved the highest reduction in population density (72.6%), followed by Spinosad (58.3%) and neem extract (37.0%), compared to the reference treatment. These findings demonstrate that integrating monitoring tools with selective and botanical control measures provides an effective and sustainable strategy for managing T. absoluta under greenhouse conditions while reducing dependence on conventional insecticides.