According to the principles of Modeling & Simulation(M&S)and charactersitic of detonation system that final performances are determined by initial conditions,total uncertainties are sorted to three parts that varying along with initial conditions.It reveals how uncertainties are brought on and evolve from benchmark models to new models.Based on engineering practices and technology of verification & validation,a framework of quantification about uncertainty is brought forward in detonation simulation.An example is presented to demonstrate general idea in quantifying uncertainty of M&S.