Leafminers (Liriomyza sativae, L. huidobrensis, and L. trifolii) are a group important insect pests of vegetable and ornamental crop production globally. Previous studies indicate that interspecific competition, and species succession and/or displacement are commonly present among different leafminer species. This review herein has reviewed the recent research progresses on interspecific competition among Liriomyza species worldwide with a special focus on Chinese literature. In addition to the review of the fast expanding literature on distribution, biology, ecology, and management of the three leafminer species worldwide, we focused on the interspecific competition and its ramifications in deciphering the possible underlying mechanisms for the competition. The key factors affecting interspecific competition, species succession and/or displacement were identified as reproduction interference, emergence of virulent biotypes, natural enemy suppression, niches of leafminers and their host crops, and pesticide resistance. Although the three invasive species of Liriomyza are the key pest species in China, their distribution patterns vary significantly. While L. sativae is distributed in all provinces in the mainland China, L. huidobrensis is distributed in majority of, but not all provinces, and L. trifolii is currently limited in the southeastern provinces (e.g., Guangdong and Hainan provinces). However, the distribution of L. trifolii is rapidly expanding among the eastern coastal provinces as the result of the development of new virulent biotypes, which is likely to be selected by frequent insecticide applications on the short-cycled vegetable and ornamental crops in the region. The dynamic changes in key ecological factors influencing interspecific competition are valuable in designing innovative management strategies for leafminers in general and to advance our knowledge of understanding ecological genetics, and plasticity of host plant adaptation, and evolution of host speciation of leafminer pest in the confined greenhouse and/or field vegetable and ornamental crop production ecosystems. This review on key ecological research status and prospects on invasive Liriomyza spp., which could be readily used as the guidelines of ecological research on other invasive pest species to identify the key factors related to interspecific competition, and consequently species succession and displacement.