When lightning strikes optical fiber composite grounding wire（OPGW）

the propagation speed of lightning current traveling wave on the outer strand is faster than that in the fiber optical. This process will produce a pseudo wave front ahead of the light polarization signal caused by lightning and thus bring a positioning error. Consequently

we proposed the concept of pseudo wave front for the first time

and studied its formation and propagation characteristics.Moreover

we simulated the formation process of lightning current traveling wave

and comparatively researched the wave formation characteristics between simulated lightning experiment and on-site lightning monitoring experiment. The results show that the pseudo head phenomenon presented in this paper does exist

and it will cause substantial impact on the positioning accuracy of lightning stroke. The farther the distance from the lightning point is

the longer the impact length of the pseudo head will be; the larger the amplitude of the lightning current is

the greater the offset amplitude of the pseudo head will be. The traditional calibration methods for traveling wave head may sometimes be inapplicable

and the research can provide a reference for the practical application of lightning location method based on OPGW.