Some thrips species (Thysanoptera) are known as major pests because of causing the damage, especially to young citrus lemon fruits. Therefore, thrips surveys were carried out in from flowering period until the fruit reached a size of 4-5 cm in diameter in Adana and Mersin provinces, Turkey. In each orchard, 100 fruits were randomly collected and checked individually to determine thrips damage on young fruits. A total of 13 thysanopteran species were determined. Frankliniella occidentalis (Pergande) was the most common thrips species on different citrus varieties in Adana province, but Thrips hawaiiensis (Morgan) dominated thrips fauna in the citrus lemon groves in Mersin province. No thrips damage was recorded in the groves where F. occidentalis was commonly present. Thrips hawaiiensis appeared to be harmful on lemon flowers and fruits. Thrips caused silvery or bronzed stains on flowers and fruits. Thrips damage was observed in the mid-May when the flower density was low i.e. third or fourth weeks following petal fall. The staining rates on fruits due to T. hawaiiensis in the sampled lemon orchards ranged from 20 to 34%.