The outbreak of Grance's debt crisis in 2009 marked that the euro zone had been tragged into a debt predicament. Later, Ireland, Portugal, Spain and Italy also had fisical troubles. European debt crisis tends to spread from the "periphery countries" to the "core countries". The main reasons for European debt crisis are external environment, internal factors and the euro-zone mechanism, but each country has its different and specific reason. The negative impacts of the European debt crisis on euro zone and the global economy include the following: decline in demand, increase in banks 'risk, and decline in investors and consumers' confidence. The debt crisis in Europe may become the main uncertainty of 2012 global economic development. <<