Abstract: Generally, the floating roof tank is heated by means of vapor tracing coil pipe. In the light of the internal corrosion of heat tracing coil pipe caused by condensation return water of floating roof tank in Alashankou Pump Station, the corrosion reason of heat tracing coil pipe is analyzed. According to analysis results, two measures against the internal corrosion of heat tracing coil pipe are worked out; one is to control the content of CO₂ contained in feed water and the other is to add volatile basifier and alkyl amine (C₁₈H₃₇ NH₂ and C₁₆ H₃₃ NH₂) to the feed water. And comparison is made to the two measures and problems existed in the aspect of prevention are pointed out.