Abstract: In order to effectively prevent frequent scaling during hot water injection development, the scaling mechanism of offshore oilfield D under hot water injection is studied, and the high-temperature resistance scale inhibitor was evaluated. Dynamic scaling experiment was applied to study the scaling rules of settling scale and suspended scale at different temperatures. The scaling product components were analyzed. The anti-scaling performance of four high temperature resistance anti-scaling agents was evaluated by calcium ion titration. The results show that scale deposition in injected water of oilfield D increases exponentially with the increase of temperature, and the scale deposition increases from 13 mg/L at the initial temperature of 60 ℃ to 37 mg/L at the design temperature of 130 ℃ hot water flooding. With the increase of temperature, the suspended scale content firstly increased and then decreased, and the scale formation increased from 94 mg/L at 60 ℃ to 1 361 mg/L at 150 ℃, and 938 mg/L when the temperature further increased to 180 ℃. The scaling products are mainly calcium, magnesium, iron carbonates and a certain amount of corrosion products of iron. Copolymer high temperature resistance scale inhibitor YFFZ636 has the best scale prevention effect, the anti-scaling rate reached 92.6% at 130 ℃. It is recommended to add YFFZ636 with a concentration of 30 mg/L before water injection heating equipment.