Abstract Background :Air quality is degraded due to an increase in air pollutant sources from human activities, an increase in the economic and technology sector followed by a high consumption of motorized vehicles and an impact on an increase in the volume of transportation, where the transportation sector is a source of human activity as a contributor to 77% of total emissions. it was also found that the use of private cars as emitters is about 80% of total traffic vehicles. Material and method.The research method uses quantitative analysis with environmental health risk analysis, population determination is taken purposively, and population objects Carbon monoxide gas concentration in the basement parking area of the basement, Graha pen and, Makassar Town square. Finding and discussionQuantitative results determine the concentration of carbon monoxide (CO) at the basement parking lot M tos shows the highest concentration measurement is at point 1 (Entrance in the morning is 16613.34µg / Nm3 and Dan for the basement parking lot Graha Pena shows the highest concentration measurement is in the middle in the morning, namely 15897.74 µg / Nm3 quantitative data analyzed by calculating the EWI, THQ and RQ values obtained for the saphiro-Wilk significance value obtained 0.016 for real-time RQ and 0.116 for 30-year RQ life time. For EWI values are weekly carbon monoxide (CO) exposure obtained an average value of 10.130 mg / kg / week and the THQ value is carbon monoxide (CO) based on real time an average of 0.3771 is obtained where carbon monoxide (CO) based on real time obtained an average of 0.3771. ConclusionTarget Hazard Quotient(THQ) real time is not adventurous because of the THQ value  1 but for a life time of 30 years carbon monoxide (CO) exposure is risky because of the values obtained from THQ 1