The effects of different biotransformation temperatures (250, 550, and 850 °C) and different dose (0-1%) of biochar on the physiological characteristics of maize seedlings under the stress of atrazine were studied. The results show that atrazine significantly inhibits the growth of maize seedlings, while biochar can alleviate the toxicity of atrazine to seedlings. Compared with the low temperature of biochar, the addition of BC850, the germination rate of maize was significantly increased. The biochars prepared at higher temperatures and adding 1% dose could significantly increase the plant height, while the effect of biochar on root growth of maize seedlings was not significant. According to the data, with the increase of biochar application, the accumulation of atrazine in maize leaves and roots gradually decreased. At the maximum application rate of 1%, the content of atrazine in maize leaves decreased by 58.94%, 60.70%, and 62.75%. The content of atrazine in maize roots decreased by 52.93%, 54.57%, and 55.42%, respectively. Meanwhile, the addition of biochar could slightly increase the chlorophyll content, but the change was not significant statistically, while the content of chlorophyll b increases with the application amount. The content of malondialdehyde (MDA) in roots and leaves decreased first and the increased with the dose of biochar from 0 to 1%. Compared with the atrazine treatment, the content of MDA in leaves and roots decreased significantly, and the lipid peroxidation of maize significantly decreased. With the addition of three kinds of biochar, the soluble content of plant tissues increased gradually, BC550 biochar has the most noticeable remediation effect. Given the toxicity of atrazine in soil, the quality and yield of agricultural products, and the potential health risks to human beings, biochar can be the soil remediation product.