Nanomedicines are complex pharmaceuticals which are produced in highy controlled manufacturing processes. They show the ability to provide targeted drug delivery, improve drug solubility and effectiveness. On the other hand they reduce a drug’s immunogenicity. Those positive factors resulted in great potential to revolutionize the treatment of many diseases. Despite the fact that nanosimilars are developed as a follow-on version to nanomedicines they show significant clinical differences which present a great challenge in defining a regulatory framework for manufacturing and registration of these drugs. This work provides an overview of most frequently used nanoparticles as an introduction to discussion on basic principles of manufacturing and marketing authorization of three different nanosimilars. First of them are nanosimilars based od polymeric micelles, second are iron oxide based nanosimilars and third are nanosimilars based on liposomes. To provide better understanding of the current state in regulatory of nanosimilars, this work provides basic principles of development of nanosimilars and evaluation on current state on the market of nanosimilars. Furthermore, in this work safety assessment of nanosimilars is discussed in detail. Due to the enormous potential and rapid growth of nanosimilars on the market, regulatory authorities need to develope a set of guidelines for manufacturing processes and marketing authorization of these medicines. Those guidelines would set a basis to greater number of safe and efficient nanosimilars on the market.