Weak couplingeffect between two optical Tamm states (OTS) in metal-DBR-metal (M1-DBR-M2) structure will occur when the periodicity of distributed Bragg (DBR) in theM1-DBR-M2 is relatively large. By studying the reflection spectrum and the distribution of the electric field of the intrinsic wavelength of OTS under the condition of weak coupling of OTS, the intrinsic wavelength, reflectivity and optical tunneling effect of OTS are revealed. The results show that the intrinsic wavelength of OTS is affected by the thickness of the metal film M1 under the weak coupling condition, while the thickness of the metal film M2 has no effect on the intrinsic wavelength of OTS. Although only the OTS1 at the M1-DBR interface can be excited, the local field phenomenon is not only localized at the M1-DBR interface. The light can go through the DBR and be localized to the DBR-M2 interface, which is optical tunneling effect. The optical tunneling effect is related to the intrinsic wavelength detuning between two OTS. The smaller the detuning of the intrinsic wavelength is, the stronger the tunneling effect is. The intrinsic wavelength detuning between two OTS also affects the local intensity of light in the M1-DBR-M2 structure. The smaller the detuning of the intrinsic wavelength is, the stronger the local phenomenon of light is, and the smaller the reflectivity at the concave peak in the reflection spectrum is.