Many complexities can be observed in the construction of tunnels for Pune metro (the second-largest city in the state of Maharashtra, India). It inherently involves many risky activities like excavation and lining, transportation of material, scaling and mucking, ventilation, cutter head intervention of tunnel boring machine (TBM) in compressed as well as in open mode, handling of tunnel machinery, working in narrow space, overloading of the crane, temporary segment dismantling, etc. Although tunneling for metro rail is risky, the risk involved is more in the longer tunnels. To save valuable resources and winning the trust of the client, risk assessment for each activity during tunnel construction is crucial. The expository literature review indicates that very few studies are available on risk assessment of each activity of tunnel construction in India using TBM. This study presents a case study on risk assessment of underground construction for the Pune metro. The work provides an insight into risk which occurs during the construction and describes general consideration for the uncertainties during execution. The paper provides the qualification and quantification for the risks in metro tunnel using risk matrix and expected monitory value (EMV) analysis. The risk matrix is the most effective tool for risk assessment and qualitative risk analysis. And EMV is succeeded using recommendations accessible in the literature of domain of risk management. Though it is a straightforward method, it is a productive application for the quantification to accomplish the goals of the metro tunnel project in terms of controlling the time delay and cost overrun as well. After the qualification of the risk process, quantitative assessment can be done for the further elected majors to choose the suitable reaction schemes. To manage the risk-associated cases efficiently. TBM data has been taken into account for risk assessment. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.