Abstract: Based on the assumption of the classical Janssen bulk solid pressure theory in vertical silos , a new theoretical equation of the pressure on silos or similar silos with dip angle is derived, which develops the using range of the classical Janssen theory and makes it a particular case of the new equation in 90° dip angle. At the same time, considering the practice of mining narrow vein in mining engineering, a new method of correcting the new equation is advanced by the simulation tests. By means of the correction on the new equation, a semi-theoretical and semi-empirical bottom pressure equation is obtained and used for mining narrow vein. The research results are of great significance to both the development of classical Janssen bulk solid pressure theory and the application of mining engineering.