The work aims to conduct an empirical study on the readability of Chinese characters used in bus stop signs, in order to provide a feasible basis for optimizing the reading of bus stop sign text information, and to enable the characters to convey information more quickly and accurately, thereby improving the efficiency of passenger transfer during bus travel. With the use of Chinese characters for bus stop signs in Baoshan District, Shanghai as the research object, an empirical study was conducted on the readability of Chinese characters for bus stop signs. Firstly, participants selected 6 characters from the 12 existing boldface characters in the market as experimental characters to form experimental samples. Further experiments were conducted on these samples to compare the readability of several boldface characters. Then, the accuracy of the conclusion was verified in the field environment. Finally, by analyzing the characteristics of characters with high readability, the elements for achieving high readability in the character design of bus stop signs were summarized. Different characters have differences in readability. The boldface characters with concise and straight shape features, a stroke thickness to height ratio of 1/9.5 to 1/10, and a central circle size similar to that of HanyiQihei-60s have high readability in the application environment of bus stop signs.