Currently the main assessment indicators for GHG emissions include national indicator, per capita indicator, per GDP indicator, and international trade indicator. Based on the GHG emission data from World Resource Institute (WRI), US Energy Information Administration (EIA), and Carbon Dioxide Information Analysis Center (CDIAC), the results of each indictor are calculated for the world and especially for the eight main industrialized countries of US, UK, Canada, Japan, Germany, France, Italy and Russia (G8 Nations), and the five major developing countries of China, Brazil, India, South Africa and Mexico, and their merits and demerits are analyzed. It points out that all these indicators have some limitations. The indicator of Industrialized Accumulative Emission per Capita (IAEC) is identified to evaluate the industrialized historical accumulative emission per capita of every country. IAEC indicator is an equitable indicator for GHG emission assessment, which reflects the economic achievement of GHG emission enjoyed by the current generations in every country and their commitments. The analysis of IAEC indicates that the historical accumulative emissions per capita in industrialized countries such as UK and USA were typically higher than those in the world average level and the developing countries. Emission indicator per capita per unit GDP, consumptive emission indicator and survival emission indicator are also put forward and discussed in the paper.