This paper discusses the global stability of a nonlinear dynamical system 

 in which 

 is a locally Lipschitz continuous off-diagonally monotone function and 

 . Two results are proved: 1) if 

 is piecewise-linear function and if 

 is an 

 -function, then a unique equilibrium point exists and it is globally asymptotically stable; 2) if 

 is a nonlinear function with separate variables in the sense that 

 is given by 

 for all 

 , and if 

 is an 

 -function satisfying 

 for some nonnegative vector 

 , then 

 is globally asymptotically stable. These results are applied to the stability analyses of a large scale composite system and a compartmental system.