One of the main challenges in Petroleum and gas companies facilities is corrosive fluid due to high sour, water cut and CO2. Corrosion inhibitors are typically injected in Carbon Steel pipeline in oil and gas production to mitigate corrosion caused by the presence of water, H2S/CO2, chloride, and acidic gas. This paper will cover latest experience in corrosion inhibitors tender qualification for all fields. The qualified corrosion inhibitor must be compatible with production fluid, and not affect the performance of other process chemicals or non-metallic seals. Testing procedures for the qualification and selection of corrosion inhibitors vary in efficiency to the pipeline’s fluid chemistry, temperature, velocity, and pressure. The procedures also change because of the different specifications and implementation approaches employed by chemical suppliers and end users. The latest tender covers all client fields in Oman which classified in five cases and six chemical suppliers participated in the tender. The tender included all series of laboratory testing and field trial in the field. The paper also describes the results of laboratory testing (pre-qualifications and performance tests) and field trial results. Furthermore, lab testing was done to qualify corrosion inhibitor for sour fluid with high velocity and shear stress 60 Pa. All stages of the tender from starting till announcing the qualified chemical supplier and all the difficulties and challenges which was in tender will be described in detail in this paper.