The invention relates to a fluorinated weather-resistant film for a solar photovoltaic battery back plate and a preparation method of the fluorinated weather-resistant film, belonging to the technical field of solar photovoltaic generation. The fluorinated weather-resistant film is used on a packaged material back plate of a solar photovoltaic battery component so as to protect the battery component from being eroded by
water vapor and preventing the oxidization of
oxygen. The formula of the fluorinated weather-resistant film comprises the following materials in parts by weight: 61-78.8 parts of fluorinated resin, 5-20 parts of
inorganic filler, 5-8 parts of
processing aid, 0.1-0.5 parts of
lubricant and 0.1-0.5 parts of antiblocking agent, and can further comprise 0-20 parts of flow modifier. In the invention, the fluorinated weather-resistant film for the solar photovoltaic battery back plate is prepared by adopting an extruding and film-blowing method. The prepared fluorinated weather-resistant film is flat, is easy to wind and rewind, has fewer black points, and simultaneously has obvious mechanical performance, especially high tearing strength and balanced longitudinal and horizontal performances. The film is not shrunk at the temperature of 120 DEG C. The transmissivity of
water vapor of the single-layer film is low.