Abstract: Objective To study the trend of the salivary testosterone concentrations in boys and girls aged 8 and 10.Methods We conducted a cross-section investigation in 468 boys and girls aged 8 and 10.Results The results showed that the salivary testosterone concentrations in boys and girls aged 10 were higher than that in boys and girls aged 8 repectively;the salivary testosterone concentrations had no significant difference in the groups of boys and girls aged 8;the salivary testosterone concentrations in girls aged 10 were higher than that in boys aged 10.