This chapter aims to highlight the effects of climate change on the invasion and displacement of copepod populations. Copepods are integral components of marine food web that serve as predators and prey. Their dietary preferences range from herbivorous to carnivorous and can even lead parasitic lives. Diel vertical migration, an important aspect of copepods, significantly contributes to carbon sequestration and nutrient cycling. Copepods can exhibit varied response to community structure, abundance, and distribution changes, making them excellent bioindicators. With the stress of increasing global warming and ocean acidification, their physiology, phenology, and distribution will change along with the rest of the ecosystems and be commercially affected by copepods as primary prey. These impacts enable invasion of new species, further worsened by increased temperatures and maritime trade. Emerging genomic studies and eDNA metabarcoding offer better strategies for managing and efficiently monitoring of these invasions. Effective strategies and collaborative efforts to consider combined effects of climate change and invasive species are necessary to mitigate these issues.