The large pine weevil (Hylobius abietis) is the most serious insect pest on coniferous seedlings. It damages them by the so-called maturity feeding. The thin bark above the root neck can be damaged to the terminal. The large pine weevil develops in conifer stupms that are present in large quantities after wind or bark-beetle calamities. Nowadays it is also widespread in protected areas where the traditional chemical method of protecting seedlings is limited or excluded, so it is important to look for new ways how to control its population. The usage of entomopathogenic fungi seems like one form of ecological control how to suppress harmfulness of this kind. This work monitors the biological effectivness of fungi on hardwood images of large pine weevil, mortality rates and infection transmission from treated to untreated individuals.