The ISO 21809-3：2 008 standard requires that PQT（process qualification test） and PPT（pre-production test）should be carried out before coating of subsea pipeline field joints. IMPP（injection moulded polypropylene）is a new type of coatings for subsea pipelinefield joints，which has complex application process and used onlyinfew projects. In order to ensure the success of IMPP coating，the requirements of standards and specifications must be strictly implemented in PQT and PPT，and all the parameters must be tested to ensure that the requirements are compliant. This paper introduced the testing process and results of PQT and PPT of the IMPP coatings in an international subsea pipeline laying project contracted by our company，and analysed the problems found in the process. Suggestions were proposed for PQT and PPT of new similiar subsea pipeline field joints. Compared with the conventional field joint coatings PQT and PPT，the test process and sample preparation process of IMPP coatings were more difficult，and special tools and equipment were needed in cathodic disbondment test and thermal aging test.