Throughout Donald Trump's use of social media in the two US elections in 2016 and 2020, there is no doubt that it has pioneered a very influential political communication strategy in the new media era, and his full use of social media has achieved remarkable results in shaping his political image and attracting public attention. It is certain that his political communications strategy has played a crucial role in helping him won the 2016 election, but even so, its defeats of the 2020 election is indisputable. The former's victory and the latter's defeat undoubtedly formed a sharp contrast. Combined with the different social backgrounds of the two elections, this paper will synthesize all kinds of data to analyze the effect of Trump's political communication on social media. While affirming its certain effect, this article will point out the defect (negative effect of its communication effect) and the limitation of its effect (inconclusive).