This study investigated the influence of birch-derived biochar (80 ton/ha) on the leaching of glyphosate, aminomethylphosphonic acid (AMPA) and phosphorus (PO4-P) in soil in greenhouse conditions. The biochar used in the experiment was produced through pyrolyses at three different temperatures (300, 375 and 475 ºC). The additional objectives were to present the interaction of glyphosate and phosphorus in soil and the effects that different variables related to a biochar production have on pesticide and nutrient leaching. The results showed that the application of biochar reduced the leaching of glyphosate by 71 % and AMPA by 36 % in soil. It was not possible to indicate which features of biochar reduced the leaching. The application of biochar did not affect significantly the leaching of phosphorus (PO4-P). The effects of pyrolysis temperatures on glyphosate and AMPA leaching were not statistically significant either. Due to the variation in the leachability and the little amount of replicates it was not possible to reliably indicate the differences between biochars. However, contrary to the hypothesis there were some indications that the biochar produced in low temperatures might be the most effective in reducing the leaching of glyphosate. The biochar obtained from a low temperature pyrolysis (300 ºC) demonstrated computationally the most significant reducing of leaching. The leaching of glyphosate and AMPA reduced 81 % and 46 % compared to the control treatment, respectively. With the amendment of 475 ºC biochar in the soil, total glyphosate and AMPA leachates decreased by 58 % and 23 %, respectively. More studies are needed to investigate the effects of pyrolysis temperatures on glyphosate leaching. Adding biochar to soil is a promising way to reduce the leaching of harmful substances. Soil-biochar additions could be an effective way to reduce leaching especially in clearly defined targets, such as drainages and the edges of slope fields. However, the interaction of biochar, glyphosate and phosphorus in soil is complicated and many things, like the quality of soil, vegetation, the features of biochar and the combined effects of substances in soil affect the interaction.