Abundance and mortality of Western corn rootworm eggs during the winter in the soil are the primary factor that determinates the potential damage of larvae on the maize roots in spring. The aim of investigation is to determine the relationship between the capture of western corn rootworm adults on baits and the estimated abundance of oviposited eggs in autumn and spring. Second aim was to describe the relationship between the estimated number of eggs in autumn and spring of next year to determine the ratio of mortality in the given circumstances. Data on the number of eggs in autumn and spring were analyzed by binominal estimate of the population number based on frequency of occurrence. Relationship between the estimated number of eggs in autumn and spring is described by linear regression model. There was a positive correlation between the data of captures of adult corn rootworm on baits and the estimated number of eggs in autumn and spring. Coefficient describes strong relationship. Linear model that describes winter mortality of eggs (y = 0,6505x - 512 586 (R.sup.2= 0,955.sup.*1) was set.