Abstract: HD190967, HD35921, HD228854, and HD100213 are early-type O or B binaries with orbital periods of 6.519 days, 4.0024 days, 1.8855 days, and 1.3872 days, respectively. They belong to the category of long-period binaries, which are rare and difficult to obtain complete light curves. The TESS (Transiting Exoplanet Survey Satellite) space telescope provides high-quality data for these four sources with its long-term, short-exposure, and high-precision photometric measurements. In this paper, we use the light extremum times obtained from TESS and historical data to analyze and study the orbital periods of these four early-type binaries. The results show that the orbital periods of all four sources are increasing in the long term, and HD228854 and HD100213 also exhibit sinusoidal variations in addition to the long-term increase. We find that the orbital period increase of HD190967, HD228854, and HD100213 is caused by mass transfer from the secondary star to the primary star, while the orbital period increase of HD35921 is caused by mass loss from the stellar wind of the primary star. The most reasonable explanation for the orbital period sinusoidal variations of HD228854 and HD100213 is the light-travel time orbit effect due to the presence of a third body.