Environmental factors exert a great effect on the occurrence of aphids and thrips, their abundance and damage done in cereal crops, as well as the time of appearance of these pests in the crops, timing of their control and means used. Species diversity of aphids and thrips in winter rye, triticale, wheat, and spring barley was identified. Variation of the abundance of the main species of aphids and thrips in the mentioned crops was determined in relation to crop growth stages and environmental factors. For the first time in Lithuania we estimated migration activity of R. padi and S. avenae using a suction trap and compared with the abundance of these aphid species in cereal crops. The experimental data obtained in this study enables assessment of damage done by aphids and thrips in winter rye, triticale and wheat crops and estimation of expedience of the application of aphids and thrips control measures. Thrips threshold of harmfulness at which it is expedient to apply control measures was identified in winter rye.