Abstract： Objective:To establishment an assay for HIV-1 intact proviral DNA assay through droplet digital PCR (ddPCR).Methods:DNA was extracted by culturing 8E5 cells, a Tlymphocyte cell line containing a single copy of integrated HIV-1 provirus. Serial diluting DNA were prepared by amplified 1-fold, 5-fold, 25-fold, 625-fold, 3 125-fold, and 15 625-fold across the HIV-1 Ψ region, env region, and eukaryotic chromosome 10 RPP30 regions, and the linear relationship was calculated and the minimum detection concentration. DNA solution of 5 μl, 3.1 μl, 2.5 μl was added to the ddPCR mixture respectively, with each dilution undergoing two batches of detection, and each was repeated four times. The intra-batch variation coefficient was detected, while the inter-batch variation coefficient was detected by the same DNA amount and different DNA amounts to determine the stability; 8E5 cell was used to detect the intact proviral content in cells.Results:The linear fitting goodness of Ψ region, env region and RPP30 region are R2≥0.999, R2≥0.993, R2≥0.996 in 6 dilutions of DNA, respectively. At a 3 125-fold dilution, the lowest positive droplets were detected in the Ψ region, env region and RPP30 region were 3, 2 and 2, respectively, the detected concentrations were 2.37 copies/μl, 1.21 copies/μl and 1.58 copies/μl. The ddPCR repeatability experimental detecting DNA showed that the Ψ region of the intra-batch variation coefficients ranged from 0.66% to 3.43%, with the inter-batch variation coefficients of the same DNA at 3.19%, 4.3% and 3.45% respectively, and the inter-batch variation coefficients of the different DNA at only 4.35%. The env region of the intra-batch variation coefficients ranged from 0.7% to 3.20%, with the inter-batch variation coefficients of the same DNA at 3.18%, 4.52% and 3.4% respectively, and the inter-batch variation coefficients of the different DNA at only 4.02%. The RPP30 region of the intra-batch variation coefficients ranged from 0.91% to 2.91%, with the inter-batch variation coefficients of the same DNA at 3%, 4.55% and 3.37% respectively, and the inter-batch variation coefficients of the different DNA at only 3.98%. The proportion of 8E5 cells containing defective provirus and the proportion of intact provirus were calculated to be approximately 90% and 45%, respectively. Conclusions:Droplet digital PCR used to detect HIV-1 intact proviral DNA, showed strong stability and provided a technical means for HIV-1 infection reservoir detection.