Mahogany (Swietenia macrophyla King) is a wood plant that has the potential to be developed in plantations. One of the factors that interfered in the development of mahogany was destructive insects. This study aimed to identify the species of destructive insects and calculate the level of damage to mahogany seedlings in the permanent nursery BPDASHL Kapuas Pontianak conducted by the survey method. Collecting insects on mahogany seedlings is identified by using insect nets and catching them directly by hand. Calculation of damage level is to use the criteria table and crop assessment category. The results showed that there were 4 species of insects which damaged the seedlings of mahogany in the nursery, namely Valanga nigricornis, Tagasta marginella, Anoplolepis longipes and Xyloxandrus sp. The number of seeds attacked as many 585 seeds from 2.176 seeds, with the level of damage to the entire pathway which is 12,39% and included in the category of minor damage. Keywords: Destructive insects, Identification, level of damage, mahogany seedlings, permanent nursery