Starch concentration is an important quality character of barley grain. In recent years, some researchers have realized that barley grain starch concentration (GSC) is affected by genetic factors, as well as by its cultivation and environmental conditions. However, the effect of different environmental factors on barley GSC remains unclear. In addition, previous studies have mostly been conducted at several sites, and large-scale studies have not addressed the relationship between cultivated barley GSC and environment factors. The Qinghai-Tibet Plateau is an important region for growing hull-less barley in China, and the relationship between barley GSC and environment factors on the Qinghai-Tibet Plateau have not been reported. Therefore, the present study investigated the distribution of barley GSC on the Qinghai-Tibet Plateau using geography, climate, soil, and agronomy data from 83 sampling sites, the cultivated barley GSC distribution characteristics in Qinghai-Tibet Plateau was studied in this research work. The aim of the study was to identify the relative effects of different environmental factors on GSC, to clarify the relationship between the distribution of barley GSC and environmental factors, and to get explicit GSC acclimation of barley varieties planted in different areas to environment. The results showed that (1) GSC exhibited a macrocosm pattern of spatial distribution along the horizontal direction on the Qinghai-Tibet Plateau, with staggered patches of different value and a tendency of "high in the south and low in the north". In addition, two regions of higher GSC (south-central and north-eastern) included the Lazi, Longzi, Duilongdeiqin, Qushui, Nimu, Dingri, Sajia, Dazi, Zhanang, Shigatse, Mozhugongka, Gongga, and Qiongjie Counties in Tibet and the Gonghe, Guide, Haiyan, and Tongde Counties in the Qinghai Province. (2) Along the vertical direction, GSC exhibited an S-shaped distribution pattern. Indeed, GSC increased gradually with increasing altitude from 3300.0-3600.0 m, reached its maximum between 4200.0 m and 4500.0 m, and thereafter slightly decreased with increasing altitude. (3) The relative effects of the environmental factors on barley GSC were as follows: spike density > average diurnal temperature range in June > length of the awn > average temperature in September > average temperature in January > annual sunshine hours > accumulated temperature (≥0 ℃) > average temperature in May > average diurnal temperature range in August > average temperature in August > average temperature in June > accumulated temperature (≥10 ℃) > average precipitation in June > average precipitation in May > average relative humidity in July > average relative humidity in August > average temperature in July. Therefore, genotype had the greatest impact on the GSC of cultivated barley, followed by climatic factors, and the effects of soil factors effect were not apparent. Spike density and length of the awn were the most important agronomic factors, and diurnal temperature range during the period of elongating and heading and average temperature during the period of filling and maturation were the main climatic factors, whereas the effects of sunshine hours and precipitation were relatively small. These findings support previous reports that barley GSC is mainly controlled by the characteristics (i.e., genetic factors) of individual barley varieties, although the effects of environmental factors were also apparent.