14 TOC mass fraction and delta~(13)C_(org) records were selected from lake sediments in arid and semi-arid regions of East and Central Asia, and the TOC mass fraction and the impact of delta~(13)C_(org) changes in their different deposition stages and their relationships were studied, which could provide a basis for the proper use of delta~(13)C_(org) in palaeoclimate research. The results showed that the changes in lake sediments delta~(13)C_(org) had been controlled by the TOC mass fraction to a certain extent. The TOC mass fraction and the corresponding variations of delta~(13)C_(org) possessed corresponding thresholds in those regions. Different threshold ranges represented different depositional patterns of TOC and the relationship between TOC mass fraction and delta~(13)C_(org) were different in different depositional models. When the TOC mass fraction became lower or higher, no correspondence between them occurred, probably organic matter was affected by an unstable sedimentary environment. Different deposition patterns of lakes might have caused the organic carbons to be different.delta~(13)C_(org) might be related to climate changes under the buried model of organic matter. Therefore, using delta~(13)C_(org) to explain climate changes should be combined with data about the sedimentary stage of organic matter.