Heavy metal fluoride glass fiber, such as fluorozirconate glass fiber, has attracted considerable attention as a new generation of optical fiber for telecommunication and as a new fiber laser material. This papar presents the preparation techniques of infrared transmitting fiber with ZrF4-BaF2-LaF3-AlF3-NaF (ZBLAN) glass as the core and with teflon FEP as the cladding. The effect of technological parameters on the scattering loss of fluoroziconate glass fiber is studied. It is shown that the glass-melting temperature, the homogenizing time, and the ater content in the environment during the glass-melting and the fiber-drawing process are very important technological parameters in order to reduce the scattering loss. Moreover, the NH4HF2 content in the batch, the temperature distribution in the fiber-drawing furnace, and fiber drawing technology also have influence on the scattering loss of the fiber. Based on these studies, the FEP-cladding fluorozirconate glass fiber with a minimum loss of 0.24 dB/m a 2.32 μm is obtaiend.