One method of determining the function of genes is a morphological, cytological and molecular comparative analysis of plant phenotypes obtained after the construction of the gene causing gene silencing or its overexpression. In this paper, an overview of the current state of knowledge concerning gene silencing with regard to its suitability for the study of gene function. Discusses the following topics: types silencing (silencing genes at the transcriptional, post-transcriptional gene silencing, co-suppression, gene silencing dependent on homology, RNA interference, attenuation), their genetic determinants and the examples of the most commonly used vectors silencing in plant functional genomics.