Today, the widespread use of organophosphorus insecticides such as chlorpyrifos in agriculture has caused serious environmental problems, and it seems necessary to provide a solution to eliminating these substances. Iron oxide nanoparticles are one of the types of nanoparticles that are widely used in the environment due to their good magnetic properties and ability to absorb pollutants. Nanoparticles are prepared in different ways. Recently, the use of green synthesis methods of nanoparticles using plant extracts has attracted the attention of researchers due to its compatibility with the environment. In this research project, the green synthesis of iron oxide nanoparticles in the matrix of polylactic acid nanofibers was prepared with the plant extract of Artemisia as an effective and cheap super absorbent for agricultural water treatment. Then, the effect of this adsorbent in the removal of chlorpyrifos poison and the effect of variables affecting absorption such as contact time, amount of adsorbent, temperature and pH in this process were investigated. Analysis of the structure of the composition showed that iron oxide nanoparticles are well stabilized in polylactic acid nanofibers and the average size of nanoparticles is 29 nanometers. Also, the results of the absorption test by nano adsorbent showed that the maximum amount of absorption to remove chlorpyrifos is done at pH=7 and with an amount of 0.7 grams of adsorbent, and the prepared adsorbent can be reused after 5 times of recycling. Therefore, it can be concluded that due to the presence of iron oxide nanoparticles, the nanocomposite made can increase the absorption capacity of agricultural toxins.