The invention discloses an underground water phreatic water evaporation measuring system and method based on an internet of things technology. The phreatic water evaporation measuring system comprises a Mariotte bottle, a lifting machine, a soil column, a gravity sensor, evaporation strength control equipment, a data collecting and transmitting device and terminal equipment. The phreatic water evaporation measuring system based on the internet of things technology disclosed by the invention achieves automatic recording, transmission and checking at any time of experiment data and greatly reduces experiment work amount; a high-accuracy sensor in the phreatic water evaporation automatic measuring system improves measuring accuracy; by means of taking effects of underground water mineralization degree on phreatic water evaporation into consideration, a phreatic water evaporation model is further corrected, and the phreatic water evaporation model is more suitable for an evaporation process of phreatic water in an area where underground water mineralization degree is higher. The system disclosed by the invention can simulate effects of different underground water levels, evaporation strengths and underground water mineralization degrees on phreatic water evaporation and is suitable for phreatic water evaporation of stratified soil and homogeneous soil.