The invention discloses a preparation method of a color temperature self-adjustable LED lamp filament based on chip scale packaging. The preparation method comprises the following steps: preparing a fluorescent glue film, preparing chip scale packaging flip chips with different color temperatures, etching a conductive line on a substrate and mounting the chips. The preparation method of the color temperature self-adjustable LED lamp filament, based on chip scale packaging, disclosed by the invention, has the benefits that different luminous flux, color temperature, color rendering index (CRI) and light color requirements can be met, the requirements of a real living environment for luminescence are met, and a user can skillfully couple required lighting effects through regulating and controlling the intensity of current on the line where the chips with the different color temperatures are arranged. Moreover, the use flexibility and the applicable range of the LED lamp filament are also increased, and the suitability for large-scale industrial production is also realized.