Advance geology exploration is an important safeguard of tunnel excavation. Horizontal drilling technology has the character of directness and exactness. For this reason, Fast Horizontal drilling technology is considered as one of the important geology exploration method. Some important factors , such as drilling position selection, drilling techniques and date treating techniques are studied, taking Qiyueshan tunnel of Yiwan railway as an example. The cooperating method of fast Horizontal drilling technology with other exploration methods is also studied.