Plant-parasitic nematodes (PPNs) represent a major threat to global crop yields, leading to a predictable annual loss of $157 billion in the agricultural sector. Further, weeds can negatively impact crop development and productivity by creating a competition with crops for nutrients and water. Nowadays, a range of potentially hazardous and poisonous chemical compounds are employed to reduce the amount of agricultural damage caused by plant-parasitic nematodes and weeds. As concerns over the risks of chemical pesticides grow, there is an increasing concern in using microbial methods to control PPNs and weeds, with biological nematicides and herbicides becoming a key part of eco-friendly management strategies. A natural alternative that has been well studied is the Streptomyces species of Gram-positive bacteria, which may yield a variety of antipathogenic chemicals, including organic compounds and metabolites. Researchers from all around the world employ a variety of techniques and strategies to identify novel bioactive substances in these bacteria. Bioactive chemicals have been shown to be effective in reducing the nematodes and weeds population that seriously endanger plants and crops. Therefore, the current chapter summarizes the negative impacts of nematodes and weeds on plant growth and development and also explores role of streptomyces as nematicidal and herbicidal agents, possible mechanisms and challenges for using streptomyces as biocontrol agent.