In order to reduce the impact of greenhouse gases on the global climate, many countries have tried to reduce carbon dioxide emissions and thus slow down the rate of global warming by levying a carbon tax. Kazakhstan, as one of the major energy exporting countries to Europe, has in recent years been continuously studying ways of imposing carbon tax with a view to converging with the European Union. By studying the taxation methods of countries that have already levied carbon tax and comparing the differences in the taxation methods of different countries, we can make a preliminary prediction of the possible ways of levying carbon tax in Kazakhstan and predict the impact on the economic benefits of oil and gas development projects in Kazakhstan under such a model. Currently, carbon tax is mainly levied according to the amount of carbon emissions from the combustion of fossil fuels, and it is used to force petrochemical and other high-carbon emission industries to carry out green energy transformation. The impact of carbon tax on the economic efficiency of overseas oil and gas development projects varies according to the way the tax is levied. Kazakhstan is likely to implement carbon tax in the next few years in order to avoid carbon tariffs levied by the European Union, and the tax cost and operating cost of upstream oil and gas development projects in Kazakhstan will increase after the imposition of the carbon tax, which will further squeeze the efficiency of the projects and possibly raise the environmental protection standards of the projects. The study of the taxation model and pricing standard of the carbon tax in Kazakhstan will help to better evaluate the economic benefits of the upstream oil and gas development projects in Kazakhstan under the new situation and provide reference suggestions for the next operation and development of the projects.