Agricultural chemicals, such as fertilizers, pesticides and polymers, are an indispensable component in the modern agricultural production but their safety for human health is becoming a major concern. This paper reviews the various types of agricultural chemicals and their impacts on the environment. Fertilizers are used for improving soil fertility and increase production. However, unreasonable use can lead to reduction in soil fertility and degradation and contamination of the ecosystem. Pesticides are mainly used for control of insects, weeds or fungi. They help maintain the crops healthy and high agricultural production. Abuse however can lead to human poisoning or contamination of the environment. Attention has been more on pesticides than fertilizers. Agricultural polymers have been increasingly used to control weeds, reduce water or soil loss. However, they are difficult to degrade in the soil and can lead to environmental pollution. Studies have shown that soil fertility can decrease over time. This review argues that unreasonable use of agricultural chemicals can reduce soil and crop qualities and cause important economic loss. and the review summarizes the current international research on these chemicals and puts forward suggestions and measures to improve the science of agricultural chemicals.