Recently, studies in autism have gained much attention. Hence, for this study, experimental methods for gait analysis in autism children done by previous researchers were reviewed prior to our proposed method. Although gait is not one of the diagnostic criteria for autism spectrum disorder (ASD), existences of motor deficits specifically abnormal gait patterns during walking could be investigated and explored further. Thus, the purpose of this study is to conduct a thorough review by previous researches related to walking gait for ASD children with specific scope defined. Here, the discussion focused on the sample sizes or subjects' database, gait analysis methods utilized, type of gait features extracted and the method used for assessment of the walking gait in ASD. At the end of this review, a new markerless based approach is proposed that will be more suitable to be used for detection of anomaly gait in children with autism specifically outside the laboratory environment. The proposed method will be based on the benchmark model of a 3D marker-based model and the proposed markerless model will be using a depth camera that will provide the three-dimensional (3D) skeleton image of the subject along with the motion sensor for data acquisition purpose.