Plastics are one of the most common and widely used materials in all branches of industry and everyday human life in modern society. Since plastic waste is dumped into the environment uncontrollably, plastics have become the biggest polluter of ecosystems on Earth. A special problem is represented by extremely small microplastic particles that are undetectable in the environment and can be biomobile or bioaccumulate in the geochemical cycle. The global concern of the world community and the interest of scientific researchers, especially ecologists, is focused on investigating the impact of microplastics in the aquatic environment, sediment and biota. Research on microplastics in the environment requires a thorough and comprehensive approach, and the results obtained cannot be compared due to the use of different methods that are still not standardized. Research includes locating areas of microplastic accumulation, sampling, particle separation, detection of the particle's chemical composition, and ultimately their effective removal. This paper provides a literature review of qualitative and quantitative analytical methods that include the identification and quantification of microplastic particles from the aquatic environment. In order to obtain reliable results, the most important step is the correct collection of samples. A Manta net is used for horizontal sampling, while a Bongo net is used for vertical sampling. Density separation methods are used to separate microplastic particles from the matrix. After that, by visual separation, which includes coloring (eye, microscope, magnification), these particles are separated according to their physical characteristics (texture, color form). The detection of microplastics implies the determination of the chemical composition of the polymer by the methods of Raman spectroscopy (RS) and Fourier transform infrared spectroscopy (FTIR). Hyperspectral imaging (HSI) and digital holography (DH) are also used in the identification of microplastics.