This study aimed to compare symptoms of autism spectrum disorder using the Childhood Autism Rating Scale (CARS) and the Social Responsiveness Scale (SRS™-2) and to investigate their influencing factors. The diagnostic agreement was 92.7%, but with a fair Kappa value (0.247). Children's verbal comprehension was related to the CARS scores, and no variables were related to the SRS™-2 scores. Generally, significant small correlations were found between the two measures in children with normal or borderline to below average verbal comprehension (rs = 0.32 ~ 0.49, p < 0.005), but not in those with impaired verbal comprehension. The CARS and the SRS™-2 may contain different explicit behaviors and collect different perspectives (i.e., those of caregivers and professionals). Therefore, they appear to complement each other.