ABSTRACT: The Alberta Infant Motor Scale (AIMS) is widely used to screen for delays in motor development in high-risk infants, but its reliability and validity in Chinese infants have not been investigated. To examine the reliability and concurrent validity of AIMS in high-risk infants aged 0-9 months in China, this single-center study enrolled 50 high-risk infants aged 0-9 months (range, 0.17-9.27; average, 4.14±2.02), who were divided into two groups: 0-3 months (n=23) and 4-9 months (n=27). A physical therapist evaluated the infants with AIMS, with each evaluation video-recorded. To examine interrater reliability, two other evaluators calculated AIMS scores by observing the videos. To measure intrarater reliability, the two evaluators rescored AIMS after >1 month, using the videos. Concurrent validity was assessed by comparing results between AIMS and the Peabody Developmental Motor Scale-2 (PDMS-2). For all age groups analyzed (0-3, 4-9, and 0-9 months), intraclass correlation coefficients (ICCs) for AIMS total score were high for both intrarater comparisons (0.811-0.995) and interrater comparisons (0.982-0.997). AIMS total scores were well correlated with all PDMS-2 subtest scores (ICC=0.751-0.977 for reflexes, stationary, locomotion, grasping, and visual-motor integration subsets). However, the fifth percentile of AIMS total score was only moderately correlated with the gross motor quotient, fine motor quotient, and total motor quotient subtests of PDMS-2 (kappa=0.580, 0.601, and 0.724, respectively). AIMS has acceptable reliability and concurrent validity for screening of motor developmental delay in high-risk infants in China.