Abstract: This paper improved the existing contact domain boundary detection algorithm based on Hi⁃C data，and proposed HiCID（Hi⁃C insulation density）algorithm which used insulation density statistics to characterize the strength change of the contact domain boundary. The HiCID algorithm embeded network enhancement technology into the pre⁃processing process to denoise the raw Hi⁃C data. Based on the enrichment abundance of insulator binding protein（CTCF）and histone modification，the domain boundary screening threshold was determined. At the same time，the right size and number of sliding windows for Hi⁃C data with different resolutions could be optimally selected. The experimental results showed that the contact domain boundary detection algorithm proposed was superior to the HiCDB algorithm in terms of consistency and accuracy，and had the characteristics of portability that did not depend on specific species，and the algorithm showed better performance as Hi⁃C data resolution increases.

Key words: chromatin contact domain, lineage commitment, network enhancement, Hi?C insulation density, CTCF