The utility model relates to the technical field of well testing data collection for high sulfur-containing gas wells, particularly to a wellhead data collecting device for variable flow well testing. The wellhead data collecting device for the variable flow well testing comprises a pressure and temperature sensor, a pressure and temperature collection device, a pressure and temperature conversion device and a data storage display device, wherein the pressure and temperature sensor is installed in a flexible pipe and connected with the pressure and temperature collection device through a thread; and the pressure and temperature collection device and the pressure and temperature conversion device are sequentially connected with the data storage display device through a first data line and a second data line. The wellhead data collection device collects the gas well data in a gas well production state, namely, reduces the influence on gas well yield due to well shutdown; and further, the safety coefficient is high, the operation is simple and convenient, the test difficulty is reduced, and the well testing safety performance is improved.