In China, diseases are frequently occurred to the early municipal utility tunnels constructed by shallowburied mining method with low construction standards. In order to solve the diseases problems of municipal utility tunnels which are characterized by small crosssection and low requirement for internal clearance space boundary, the maintenance and reinforcement process of a shallowburied mined cable utility tunnel in Dalian is analyzed by disease detection and analysis, comprehensive scheme comparison and construction practice. Some main conclusions are drawn as follows: (1) The tunnel disease detection should be carried out in detail from the aspects of structural deformation, lining strength, behind lining, cracks and water leakage to analyse the causes and degradation grade. (2) Rational structural reinforcement methods should be selected according to detection and analysis results; adding reinforced concrete lining is the first choice for severely degraded municipal utility tunnel. (3) Attention should be paid to the waterless construction environment, protection of existing structure and internal pipeline, and construction in small space.