Abstract: The consumption amount of organic fertilizers increased annually in Zhejiang Province. In order to prevent heavy metal pollution in agricultural fields caused by organic fertilizers application， the pollution status of heavy metals in organic fertilizers sampled in spring and summer of 2013 were investigated. The results showed that heavy metals pollution was common in commercial organic fertilizers. Contents of heavy metal in livestock manure were related with their sources and sampling seasons. In the samples collected in spring， the qualified rates of heavy metals were 34.88%， 85.00%， 78.57% and 53.85% in pig manure， cattle manure， chicken manure and mixed manure， respectively. In the samples collected in summer， the qualified rates were 67.57%， 100%， 93.33% and 83.33%， respectively. Over standard of heavy metals in pig manure was the most serious. Among 7 heavy metals， the exceeding standard rate of As in organic fertilizers was the highest. The exceeding standard rate of As in spring and summer were 58.14% and 24.32%， respectively. The heavy meatal contents of organic fertilizers in spring was significantly higher than those in summer， and the qualified rate in spring samples were lower than that in summer. Besides， it should be noted that the concentration of nutrients and organic matters in organic fertilizers produced from different raw materials showed significant differences. Indeed， the pig manure fertilizers exhibited the highest nutrients content， while the cattle manure fertilizers exhibited the highest content of organic matter. Most organic fertilizers collected in spring and summer were alkaline. In conclusion， excessive use of organic fertilizers for long\|term may bring in heavy metal contamination risks. Thus， it is necessary to carry out long\|term monitoring of heavy metals in organic fertilizers as well as reasonable application strategies.

Key words: organic fertilizer, animal manure, heavy metals, nutrient