Pinus sylvestris var. mongholica is one of the major vegetation restoration trees in the northern sand-prevention belt of China, which plays a vital role in the sheltering of wind and sand fixation, regulating regional microclimate, and maintaining ecosystem stability. 【Objective】This study seeks to clarify the dynamics and controlling factors of transpiration in P. sylvestris plantations in water-limited sandy regions and provide a scientific basis for the reasonable construction and sustainable management of artificial plants. 【Method】This study used the thermal dissipation probes, soil moisture sensor, automatic weather station, and groundwater level monitor to continuously observe the sap flow density, soil moisture content, meteorological parameters, and groundwater level in the sandy region of Yulin City, northern Shaanxi Province. With this design, we aimed to reveal the characteristics and controlling factors of transpiration water consumption of P. sylvestris. 【Result】Results showed that: (1) The sap flow density of P. sylvestris increased initially and then decreased during the monitored period (May 2021 to October 2021). On a sunny day, the sap flow density displayed an unimodal curve and had a relatively high peak value; however, on cloudy and rainy days, the sap flow density varied irregularly and had relatively low peak values. (2) The sap flow density was most sensitive to the changes in wind speed and air temperature, followed by groundwater level fluctuation. (3) The average daily transpiration rate of P. sylvestris was 0.67 mm·d-1, and the total transpiration water consumption in the growing season was 147 mm. 【Discussion】The seasonal variations of meteorological parameters (vapour pressure deficiency, wind speed, air temperture, photosynthetically active radiation) and groundwater level and the associated changes in soil water content were the main factors controlling the dynamics of transpiration water consumption of P. sylvestris. The study results can provide theoretical guidance for high efficient use of water resources and sustainable management of sand-fixing plants in the sandy region.