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Vortex flowmeters may exhibit inaccurate readings during use. After analyzing various causes, it was found that they are mainly related to selection, installation, and parameter setting; therefore, corresponding solutions are proposed for these three aspects. 1. Selection: When choosing the diameter for vortex flowmeters, users often opt for a larger diameter due to changes in process conditions; however, in practice it is advisable to choose the smallest possible diameter in order to improve measurement accuracy. A vortex street pipeline is designed to serve several devices; since some of the equipment in the process system is not used at times, the actual flow rate in use is reduced. As a result of this, the diameter selected in the original design is too large, which effectively raises the lower limit of the flow rate that can be measured. The gauge cannot provide accurate readings when the flow rate is low, but it still functions properly when the flow rate is high. Renovating the pipeline is often too difficult, as changes in process conditions are usually temporary. 2. Installation: The main issue is that the length of the straight section in front of the sensor is insufficient, which affects the measurement accuracy. Therefore, when installing a vortex flowmeter, it is necessary to pay attention to reserving an appropriate length of straight pipe section. 3. Parameter setting: Vortex flowmeters often exhibit incorrect readings due to faulty parameters. Such errors cause mistakes in the calculation of the full-scale frequency of the secondary instruments; if the actual full-scale frequency differs slightly from the calculated value, the readings remain inaccurate over time. When the actual full-scale frequency is much higher than the calculated value, the readings fluctuate significantly, making it impossible to obtain accurate readings. Moreover, inconsistencies in the parameters provided in the documentation affect the final determination of these parameters. Generally, it is necessary to determine the parameters by recalibrating and making comparisons in order to solve this problem.