Nowadays, a big part of chemical industry is focused on manufacture of pesticides for purpose of enabling agriculture, and other similar industries, to satisfy needs of a big population on Earth. That manufacturing process is associated with a problem of taking care of products which are developed by pesticides activity as well as a problem with pollution which they produce. Pollution caused by pesticides implicates contamination of natural water and soil so in order to protect and purge them there is an increasing use of methods like nanofiltration (NF). Purpose of this research was to examine the removal and removal mechanisms between selected pesticides (thiamethoxam, imidacloprid, clothianidin, acetamiprid, oxadiazon, thiacloprid and tri-allate) and 6 different nanofiltration membranes (DK, HL, KH, DL, NF90 i NF270). Pesticides were selected because they are listed on Watch list of substances for Union-wide monitoring in the field of water policy pursuant to Directive 2008/105/EC of the European Parliament and of the Council. Results obtained have shown wide range of removal of listed pesticides (from 6% to over than 97%) which has greatly depended of their molecule mass, i.e. size of molecule, log Kow, the polarity of molecules, i.e. their dipole moment, flux that was measured, the size of membrane pores and hydrophobicity of membrane. Membrane characteristics were detected by determining contact angle (determining hydrophilicity/ hydrophobicity) and zeta potential (charge of membrane surface). In fact, the greater the hydrophobic character of pesticide was, the better the bonding was on a membrane surface, which was proved with analysis on FTIR. In conclusion, the greater separation factor is achieved with pesticides that have bigger molecule mass, especially if for process are used NF membranes with big hydrophilic character.