Transformation markers offer a tool to distinguish the genetically modified insects from wild types. Both the identification of transformants and the maintenance of transformed lines depend on reliable transformation makers. In addition, the evaluation of the genetic stability of released genetically modified insects needs strong and stable markers. Thus the development of broadly applicable, easily detectable and reliable transformation markers will facilitate the study of genetic pest management. In general, eye color genes, drug resistance genes and fluorescent protein genes can be used as markers in genetically modified insects. The first efficient identification of a non-drosophilid insect transformation line was based on the rescue of eye color mutant phenotypes. However, for most insect species, the application of eye color markers is limited because of the lack of suitable recipient mutant strains and less information on related genes. Markers based on drug resistance genes can improve the screening efficiency of transformants, but the selection for drug resistance is problematic and prone to have false positives or negatives with potential biosecurity problems. Fluorescent protein gene markers significantly facilitate the development of stable insect transformation lines. The green fluorescent protein (GFP, isolated from the jellyfish Aequorea victoria) and its variants with various fluorescent characteristics can be combined with suitable, strong promoters to serve as transformation markers for a wide range of insect species and guarantee the reliable screening of the transformants. In this category, the enhanced green fluorescent protein (EGFP) was mostly used. Besides, the red fluorescent protein (DsRed), isolated from the mushroom coral, Discosoma striata, provides a selection of red fluorescent proteins with better performance than GFP mutants. This paper reviews the history and status of transformation markers including eye color genes, drug resistance genes and the fluorescent protein genes. The potential roles of transformation markers in genetic pest management are also discussed.