The use of genetically modified seeds is a controversially discussed topic. Regardless of the increased global significance - in 2006 genetically modified (GM) seeds were used on 102 billion hectares - GM seeds have almost no importance in German agriculture. However, the market introduction of Bt-corn is in its first stage. This article analyses attitudes and intentions of German farmers. The results are based on a survey of 370 German farmers which own larger structured farms in the northwest of Germany. The sample shows no clear rejection of GM seeds. A structural equation model reveals important parameters influencing the attitude and intention concerning green genetic engineering. The attitude may be explained by the acceptance within the social environment (family, village community) and by the assessment of the economic advantages. The planned behaviour is mainly influenced by the general attitude towards genetic engineering, the economic environment and by the social environment.