Abstract: To meet the sealing requirement of high pressure squeezing operations,a new type of tubing pressure test apparatus was developed. This apparatus was composed of sliding sleeve switch,sidewall channel,ballseat and spring.A ball with 28 mm diameter was firstly cast to the bottom of the ballseat to carry out tubing pressure test,and then a 45mm ball was cast to the top of the ballseat.The sidewall channel was opened at the working pressure to conduct high pressure squeezing operation.The new apparatus could accomplish the pressure test with one testing string.The field operation with this apparatus was quite convenient,and pressure test could be conducted with the tubing before the operation,and the pressure could be increased to any allowable scope.The string can meet the requirement of long-term squeezing operation.