All earth's ecosystems are contaminated with micropiastics, which in the end most often reach humans as well. This work presents the results of research conducted to determine the presence of microplastics and nanoplastics in salt and fresh water bodies. Microplastics can be defined as tiny plastic particles smaller than 5 mm, while nanoplastic particles have dimensions of less than 1 μm. According to the chemical composition, microplastics are diverse, and originate from many different types of products and can be of different sizes, colors and morphologies. There are two types of microplastics: primary microplastics that reach the environment by direct discharge from industries or household products, and secondary microplastics that result from the degradation of plastic waste in the environment due to environmental factors. Composed of various polymers, microplastics includes a wide range of chemical additives. Previous research shows that most micropiastics are found in surface waters from which, by circulating, they can spread to all parts of the environment. Research on the occurrence of microplastics and nanoplastics in the environment has been conducted only in the last ten years, and the data and findings collected so far indicate that their occurrence in the environment has a very negative impact on the living environment, so further research is needed, as well as tracking quantities in which they occur in nature.