Abstract: Based on adequate investigation of related specific work conditions of the oil field, the company has successfully developed a hi-strength special casing for service in thickened oil hot well, namely TP110H casing.Described here in the article are the main aspects concerning the said casing, covering the development background, property targets, basic manufacturing processes, property test results and the feedback from the oil field end-users.Relevant operation practice leads to such a conclusion that the developed TP110H casing has been fully in compliance with the requirements for the work conditions of thickened oil hot well, i.e., well depth:approximate 1 500 m;steam temperature:375℃ and steam pressure:21 MPa.