Abstract: FO-152 packer using in steam injection well was developed with novelty design, unique structure and thread seal method. It cancels the telescoping string, and dynamical piece is made from memory alloy. The packer also has performance seal character. The development, work principle and specialty and field using instances of this packer are discussed. Practices indicate that this packer has simple structure and reliable function. Better effect, such as saving cost, reducing casing damage and enhancing steam injection quality, have gained when is being used. The state patent number of the packer is 00252598.4.