AbsUaet--Tbe problem of a centrally cracked rectangular plate is taken as a sample problem to evaluate the dependence of the stress intensity factor on the loading condition. The total loading applied on the upper and lower edges is assumed to be 2bp (2b--the width of the plate). With the condition of the same total applied loading 2bp along the upper and lower edges, the following conditions are imposed: (a) uniform tension with intensity p, (b) a pair of concentrated forces with intensity bp, (c) a type of tension-compr.~ssion loading. A novel weight function approach is used to evaluate the stress intensity factor at the crack tip. From the numerical solution it is found that, with the condition of h/b = 3.0 (h/b being the height width ratio of the plate) the maximum deviation of the stress intensity factor from the uniform tension case is 5.8% in the concentrated force loading case, and with the same condition the dependence of the stress intensity factor on the loading condition is negligible in the tension-compression loading case. However, in the case ofh/b < 1.5, the relevant dependence is significant. Copyright (ยข.3 1996 Elsevier Science Ltd.