The invention provides an MLE and Monte Carlo simulation-based satellite life prediction method. The method comprises the following steps of: dividing satellite failures into random failures and lossfailures, establishing a life model of a random failure product, solving a mean time MTTF before the first fault of random failure of a satellite system by adoption of a Monte Carlo simulation methodaccording to each single machine failure rate and reliability logic relationship of a satellite random failure product, and obtaining a random failure reliability function Rrandom(t) of the satellitesystem; establishing a life model of a loss failure product, calculating a mean value and variance estimation of satellite loss life by utilizing the Monte Carlo simulation method according to a reliability logic relationship of the single machines, a loss life mean value and a variance and obtaining a loss failure reliability function Rloss(t) of the satellite system; and comprehensively analyzing random failure and loss failure functions of the satellite system so as to obtain a mean task duration time MMD of a satellite, and taking the mean task duration time MMD as a life prediction resultof the satellite system. The method is correct and objective in calculation.