High performance optical diode-like devices are highly desired in future practical nano-photonic devices with strong directional selectivity.We demonstrate a kind of giant broadband reciprocity optical diode-like devices by simultaneously using the directional Mie scattering effect and the asymmetric grating diffraction effect.The maximum asymmetric subtraction and the asymmetric transmission ratio can reach nearly 100％ and 40dB at specified wavelength,respectively.In a wide waveband from 500hm to 800hm,the asymmetric subtraction and the ratio keep larger than 80％ and 3.5dB,respectively,even under oblique incidence.To the best of our knowledge,this is the best one-way-transmission effect observed in the reciprocity optical diode-like devices.In addition,we further demonstrate that this one-way-transmission effect can bring an effective absorption enhancement on gold films.The giant,broadband and angle-insensitive one-way-transmission effect demonstrated here is far beyond the well-known anti-reflection effect in the light-trapping devices and will bring new design philosophy for nano-photonic devices.