A Dissertation Submitted to Mzumbe University, Dar es Salaam Business School in Partial Fulfillment of the Requirements for the Award of Master's of Science Degree in Procurement and Supply Chain Management (PSCM)The number of passengers of Dar es Salaam Commuter Train has been decreased day to day and suspensions of services due to mechanical faults make operation to be hard. In this context, this study examined the factors that would influence good services as well as attracting more riders to commuter train to achieve sustainability in reducing traffic congestion in the city of Dar es Salaam. Since it is the only Commuter Train provider in Tanzania, the sustainability in reducing traffic congestion in the city of Dar es Salaam depends on the number of riderships or passengers and how Dar commuter train can be improved in its service. So a better understanding of train commuter travel behavior will enable the enhancement of commuter rail services to increase ridership and achieve some of the sustainability goals that government and TRL are trying to. Data from respondents in six selected Dar Commuter Train stations were used to assess the sustainability in correctly classifying service status via quality, reliability, comfort, and station facilities. Dependent variable in this study was sustainability in reducing traffic congestion and independent variables considered were quality of service, reliability of the train travel comfort, and station facilities. Data were collected through primary and secondary data. A random sample of 200 commuters was chosen for this study on board the train and those waiting for the train were interviewed using structured questionnaires and among them 165 were finalized for final analysis This result based on the customer perception and it was found that passenger’s perception on comfort (81.6%), and quality of the service 71.5% of the commuters agreed with the service offered by Dar commuter train but very poor conditions of station facilities 28% are available, 51% of commuters said the service is not reliable. All these two among four variables couldn’t attract more passengers to use train. Several recommendations have been made to improve the Service of Dar commuter train so as to reduce congestion by attracting more passengers even the user of automobile to shift to this mode, includes the use of modern equipments, government intervention etc and the study shows that the train will be sustainable if some improvement must be done.