The carbon storage capacity of the Mongolian Plateau (MP) is easily ignored compared to other ecological services, due to its vast steppes and diverse arid and semi-arid landscapes. However, the impact of Land Use/Land Cover (LULC) changes on carbon storage (CS) remains unclear, limiting climate-adaptive land policies. This research combined with the PLUS and InVEST models to assess the dynamic characteristics of LULC and CS in the MP from 2000 to 2030, and introduced the elastic coefficient to quantify the CS changes caused by LULC change. These findings indicate that the CS in the MP were 21.45 Pg, 21.51 Pg, 21.70 Pg and 21.82 Pg in 2000, 2010, 2020 and 2030 respectively. Among various LULC types, grassland CS made up approximately half of the total CS during 2000-2020, yet degradation causes a carbon loss of 10.43 Tg. The largest reduction in CS mainly stems from the reduction of forest, leading to a loss of 35.57 Tg. Conversely, the land restoration by the conversion of barren land to grassland led to the greatest increase in CS, with a growth of 291.15 Tg. It reveals that the LULC dynamic changes on the MP caused carbon loss was marginally less than the carbon increase, and the capacity of the regional carbon sink can be effectively increased through land restoration measures, such as reforestation, returning grazing to grassland and desertification control.