An important trend in the field of floriculture is the creation of new varieties of ornamental plants, among which varieties with unusual color are most in demand. To this end, traditional breeding and selection programs have been successfully applied for many years. However, currently genetic engineering is able to offer an alternative way to obtain new forms and varieties. Anthocyanins belonging to flavonoids, betalains and carotenoids are the main types of pigments that are synthesized in the plant and are responsible for the color of flower petals. The modification of pigment biosynthesis pathways using genetic engineering techniques can produce results that cannot be obtained by traditional breeding. This review presents the main advances in the application of genetic engineering techniques in floriculture using the example of flower color modification. There are several main areas of work with the genes of pigment biosynthesis. Among them, the strategy of suppressing gene expression is used most often. Expression of certain genes is suppressed to prevent pigment synthesis, or vice versa, to eliminate factors that hinder color development. The method of additional heterologous genes insertion to plants lacking them in the pathway of pigment biosynthesis is often used. Genomic editing, in particular by using the CRISPR/Cas system, is also used for color modification, but the application of this method to ornamental plants is a relatively recent innovation. Despite the rapid development of biotechnology, there are obstacles to the distribution of genetically modified plants on the world market. By addressing a number of problems, the production of transgenic ornamental plants may become economically more cost-effective and attractive than the development of new varieties exclusively through traditional breeding methods.