The present invention belongs to the field of biomedical material, and is particularly related to a method of preparing bioactive glass coatings by liquid precursor thermal spray. The objective of the present invention is to overcome the shortcomings of the air plasma spraying where the powder feedstock preparation is complicated and time-consuming, and sol-gel or other wet chemistry method where the synthesized coating generally has thin coating thickness and with low production efficiency. Therefore, a new method is provided for preparation of bioactive glass coatings. In this method, organic and inorganic raw materials were first weighed in accordance with the chemical composition of bioactive glasses, and sol or suspension was prepared; then the sol or suspension was used as the feedstock for thermal spray, and was deposited on the biomedical materials substrate, at high temperature to form the bioactive glass coating. The invention possesses the following advantages: simple operation, less complicated procedures, synthesis with high efficiency, low production cost, suitable for industrial production, and so on. This method can be used to prepare bioactive glass coatings.