To obtain the laws of pedestrians' crossing behaviors, especially children, this paper analyzes the characteristics of four crossing behavior (crossing speed, waiting time before crossing, running across the street. not looking before crossing) of three groupa of pedestrians (adults, adu't-child pairs, and children alone) at unsignalized mid-block crosswalks.579 pedestrians are recorded. The data are analyzed by mean, analysis of variance (ANOVA), and Chi-Square test. The results how that; 1) pedestrians crossing speed on the second half of the crosswalk is systematically faster than the first half; 2) children's behaviors are influenced by adults and children rely on their parents: 3) children often feel overwhelmed because of the difficulty judging when how to cross the street. Children's crossing behavior should be considered when people plan and design the crossing facilities children may use. And is necessary fo prove children's skills of crossing street.