Abstract: The change of temperature of oil transported and ambient temperature result in t he wax deposit, whichdecreases the standard volume of pipe-type meter prover and proving precision of flowmeter. This paper analyzes the process and condition of wax deposit, describ es the influence of wax d eposit on the internal wall of pipe-type meter to proving result and accuracy of flowmeter and gives the mea sures to be taken to avoid the wax deposit of pipe-type meter.