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On the basis of a nonlinear constitutive model of magneto-thermo-mechanical coupling for giant magnetostrictive marerials (e.g.,Terfenol-D) and a linear piezoelectric relation,a nonlinear magnetoelectric (ME) coupling effects model of magnetic energy nanoharvester is estanlished by considering surface and nonlocal effects as well as demagnetization effect.Then,in order to reveal the temperature-dependent nonlinear coupling relation between temperature and ME coupling effects,the influence of temperature environments on the ME coupling effects of Terfenol-D-PZT-4-Terfenol-D magnetic energy nanoharvester is ftrst investigated for coupled flexural and extension modes due to the asymmetry of the trilayer composite.Results show that the ME coupling effects have obvious temperature-dependent characteristic owing to the ME device is operated in extreme temperature environment,such as space stations,satellites,and so on.That is to say,the ME coupling effects increase monotonically at the beginning,to a peak,and then decrease quickly and approach zero when the temperature rose to the Curie temperature (Tc =383.3 ℃).Meanwhile,it is discovered that the optimal ME coupling effects and temperature that corresponds to the peak of the ME coupling effects are quite sensitive to the magnetic bias.In other words,the small magnetic bias not only strengthens the ME coupling effects significantly at low temperature environment,but also improves the stability of ME coupling effects at high temperature environment.On the contrary,the strong ME coupling effects need to be derived by a relatively large magnetic bias at high temperature environment.Moreover,applying a relatively large magnetic bias could effectively resist the fluctuations in the ME coupling coefficients that were caused by low temperature.Finally,this study also reveals that the peak value of the ME coefficient decreases monotonically and the ME coupling coefficients curves shift to the right overall with an increase in the magnetic bias field.This study will provide a theoretical basis for the design and application of high performance multiferroic laminated nanostructures and magnetoelectric nanodevices which are operated under extreme temperature conditions.