In this paper,we obtain the recur sive relations of the wave function probability amplitude about the system consi sting of k independent Jaynes-Cummings (J-C) models under resonance condition by inductive method,and give the analytic solutions of the wave function in any arbitrary initial states. We focus on the properties of entanglement dynamics about the system consisting of three ind ependent J-C models under resonance condition.Th e results show that the entanglement of atoms in system is related to the number of photons of cavity field in the subsystems.The time for entanglement among atoms to die for the first time speeds up as the number of photons increase. At the same time,it is found that the entanglement of the atoms and the entanglement of the quantum fields have periodic changes with time evolution when the quantum fields of thre e subsystems are in the vacuum states.When entanglement of atoms reaches the minimum of zero,entanglement of cavity fields reaches the maximum value of one, achieving the transform of entanglement between atoms and cavity fields.