Betaine is a useful compound that has various activities and is the marker compound of Lycium chinense fruit in Korean Pharmacopoeia. we seek to support the stable production of medicinal goji berries, which have significant potential in the pharmaceutical industry due to their high values, and to provide foundational data for consistent quality control. This study's purpose was to examine the correlation among betaine content, environmental variables, and the growth characteristics of L. chinense fruits. The fruits were collected from 25 cultivation sites across South Korea. We investigated five growth characteristics and betaine contents in L. chinense fruits and twelve soil physicochemical properties, and seven meteorological data at cultivation sites. The fruit's growth characteristics included a length of 15.62-26.49 mm, a width of 7.09-11.38 mm, a fresh weight of 0.73-1.62 g, and a sugar content of 11.10-19.62 Brix°. Its betaine content ranged from 0.54% to 0.97%. The betaine content was positively correlated with electrical conductivity (0.327 **), exchangeable potassium (0.314 **), and sodium (0.259 *) and negatively correlated with annual average minimum temperature (-0.256 *) and annual average temperature (-0.242 *). Also, betaine showed a positive correlation with the length of the fruit (0.294 *) and the fresh weight of the fruit (0.238 *). These results can be used to find the best cultivation method and to manage quality control for the highly economical L. chinense fruit.