Using ferric chloride hexahydrateand zinc chloride as raw materials，and utilizing the self-assembly of polyethylene glycol 4000 as a surfactant, ZnFe2O4 nanoparticles with a hollow structure were synthesized in one step by a soft template hydrothermal method. The phase and morphology of the samples were characterized by XRD, XPS, FE-SEM and TEM, and the magnetic properties of the samples were investi-gated by vibrating sample magnetometer (VSM). A vector network analyzer was used to test the electro-magnetic parameters of the sample, and the reflection loss of the samples was calculated by simulation to study the absorbing performance of the sample. The results show that the as-prepared hollow ZnFe2O4 has a particle size of about 100 nm, is uniformly dispersed, and has a clear hollow structure. The absorbing properties are excellent, when the matched thickness of the sample is 2.7 mm, the minimum reflection loss(RL) at 12.41 GHz is up to -42.18dB; And when the matched thickness is 3.0 mm, the effective ab-sorption bandwidth( RL≤-10 dB,90% absorption rate) is 2.60 GHz (10.60GHz~13.20GHz).