A multi-sectional airtight seal for continuous air-filling includes: an input passage; plural first sub-tubes aligned parallel to a lateral side of the input passage; plural first valve devices including a first filling passage and a second filling passage with the first filling passage connecting the first sub-tubes and the input passage; plural second sub-tubes serially connecting the first sub-tubes; and plural second valve devices for connecting the second sub-tubes and the second filling passages to allow through-linking between the second sub-tubes and the input passage. When external air in the input passage enters through the first filling passage of the first valve device to fill and expand the first sub-tubes, the second sub-tube is filled through the second filling passage and the second valve device to be expanded as well.