Abstract: The method is investigated for characterizing the short fatigue crack （SFC） behaviour of 1Cr18Ni9Ti weld metal by the "effective short fatigue crack criterion" （Fatigue Fract. Eng. Mater. Struct., 1999, 22: 459-468）. Three considerations are given. Firstly, the dominant effective short fatigue crack （DESFC） behaviour is a result of the interaction and evolution of the collective SFCs and, therefore, it is deemed suitable to describe their collective behaviour. Secondly, the significant character of microstructural short crack （MSC） regime and physical short crack （PSC） regime for the behaviour of SFCs indicates that it should be well exhibited in the characterization. Thirdly, the stronger irregular behaviour of SFCs indicates the single parameter of cyclic stress or strain amplitude for representing driving force of DESFC growth may be not appropriated. A new growth law for the collective SFCs is derived from a consideration of the local cyclic strain energy density driving the DESFC initiation in the initial zone and, then, driving the DESFC growth in the zones around its tips. The final form of this law is relative to the total cyclic strain energysity of remote fields, which circle the initial zone and, then, the zones around the DESFC tips. Availability has been indicated by an analysis of the test data of present material.