With the rapid economic development in China,environmental pollution, climate change and relevant problems are becoming increasingly prominent. The model of economic development relying on fossil energy consumption results in environmental pollution and carbon dioxide emissions that show an increasing trend. Thus,it has an adverse effect on China' s sustainable development at a certain extent. In order to solve this problem,the Chinese government makes efforts to transform economic developing way and increase environmental protection investment,urban environmental infrastructure investments, old industrial pollution source governance investment and construction project ' Tri-Simultaneity' investment. However,the fact shows that the effectiveness of environmental protection investment is in question and environmental pollution and carbon emissions are still severe. In the background of environmental crisis and climate change,environmental pollution treatment and carbon emission reduction will be the inevitable trend of China's future development. Based on the panel data of 30 provinces of China during 2004-2012,this paper uses the fixed effect model to examine the influence of urban infrastructure investments to environmental treatment and carbon emission reduction. Results show that the investments in urban infrastructure and old industrial pollution source treatment do not improve environmental quality and carbon emission reduction. It is also found that total carbon emissions are not reduced by ' Tri-Simultaneity ' investments of construction project. However,growth rate of carbon emissions maintained the decline rate by 3.8% per year, indicating the obvious improvement on environmental quality in China. Our spatial analysis draws a similar conclusion. Therefore,' Tri-Simultaneity ' investments of construction project are playing an active role in pollution treatment and carbon emission reduction in future. The policy implication is that government should improve the efficiency of environmental protection funds by reasonably arranging the structure of environmental protection investments,develop construction project 'Tri-Simultaneity' investment and increase its ratio to environmental protection investment. Thus,a rationalized space structure of environmental protection investment can be achieved.