Parameter uncertainty of measurements is nominally an experimental value fluctuating around a true value in the condition of a definite confidence level. This is a very important tool for describing the accuracy of parameters besides error measures. The concept of uncertainty measurements is developed that multivariable parameters uncertainty is proposed. The basic property of generalized uncertainty is discussed later. Both the propagating characteristic of generalized uncertainty in the complex system and the classification of the propagating characteristic are investigated. The property and mode of parameter uncertainty propagation in one single subsystem are very important research contents. There is significant influence on the calculating result and the absolute value of the elements in the propagation matrix. The comparison between all the subsystems′ parameters uncertainty propagation is discussed, and the corresponding criterion is simultaneously achieved. The examples show the effectiveness and feasibility of this theory when it is applied in the parameter uncertainty propagation problem for a complex system.