The fatigue crack in bridge deck is one of the most important defects of steel box girder

which endangers the safety and service life of bridge. The cracks are classified according to their locations and propagation directions. The main causes of fatigue crack in bridge deck of steel box girders includes structure stress state

stress concentration effect

vehicle overload

manufacturing defects

etc. This paper puts forward several reparation methods by welding

such as gauging and repair welding directly

welding with backing

and welding after replacement of partial members. The applicability of different methods by considering the types of cracks

development degree of cracks

and the construction conditions of bridge site is discussed as well. And supplementary measures should be taken if necessary. The key points of detecting and locating of cracks

selection of welding procedures according to specific situations

and detail treatment are summarized. This paper can be the reference for the establishment of crack reparation methods in different situations.