Characteristics of vertical one-dimensional infiltration of soil water in three soils under different negative hydraulic heads were analyzed through a laboratory simulation experiment. Based on the Brook-Corey model, coupled with the Darcy law and the Richard equation, theoretical relationships were developed to describe cumulative infiltration, infiltration rate, wetting front and infiltration time of vertical one-dimensional infiltration of soil water under a boundary condition of negative hydraulic head. With the help of the data obtained in the infiltration experiment, relationships between these variables were analyzed, and fitness of the Philip infiltration equation under negative hydraulic head was verified. Results show that these theories can be used to better describe the characteristics of vertical one-dimensional infiltration of soil water under negative hydraulic head.