The invention discloses a fault propagation risk analysis method and prevention and control method based on a meta-motion chain, and the method comprises the following steps: decomposing the functionsof a whole machine into a plurality of motions through employing an FMA function decomposition method, and further decomposing each motion into a meta-motion; determining the subordination relation of the meta-actions in each motion, and establishing a meta-action chain formed by connecting the meta-actions in the motion in series according to the motion transmission relation from the power source of the motion to the action executing mechanism; and then establishing a risk propagation model under a common influence condition according to the spontaneous probability of the internal influenceof the meta-actions and the coupling strength of the quantitative external action, and comprehensively analyzing the risk criticality of each meta-action from the perspective of global risk influence.According to the method, on the basis of the reliability analysis idea of the meta-action chain, after the weak link is determined, the fault diagnosis work of the meta-action unit forming the meta-action is clearer, the vain fault search in the fault diagnosis is reduced, and the fault diagnosis efficiency is improved.