In order to dissolve the corrosion and scaling problems of injection-production string for the Dagang gas storage，through the optimization of a variety of functional additives，such as density regulator，corrosion inhibitors，deoxidizer，scale inhibitors and fungicides，a kind of self-healing annulus protection fluid（SHAPF），whose density can be adjusted within 1.0—1.6 g/cm³，was developed as follows：base solution +5% imidazoline corrosion inhibitor GL-3（imidazoline dithio phosphate as main component）+ 2% oxime deoxidizer dimethyl ketoxime（DMKO）+1% bactericide 1227（dodecyl dimethyl benzyl ammonium chloride）+1.3% organic phosphate scale inhibitor ZC-21 （ATMP as main component）+ 0.01% pH regulator （sodium carbonate）. Corrosion inhibition property，oxygen removal performance，sterilizing performance，scale inhibition performance of SHAPF and effect of SHAPF on the performance of the packer rubber tube of was examined. The experimental results showed that，the corrosion rate of steel sheet in the SHAPF could be as low as 0.045 mm/a，oxygen in the solution could be reduced to 40 mg/L，the sterilization rate could reach up to 100%，the anti-scaling rate of the SHAPE to CaCO₃ and CaSO₄，BaSO₄ scale could reach as high as 99%，93% and 81% respectively，and the SHAPF almost had no effect on the packer rubber tube. The SHAPF could buffer effectively hydrogen ions dissolved by acid gases and remain the related properties. Hence，the SHAPF can achieve the goal of effective protection of tubing and casing and is suitable for application in the acidic gas reservoir.