Objective: One of the most important issues in the development of fundamental motor skills in the early years of life is development of fine and gross motor skills. The aim of this study was fine and gross motor skills assessment and the relationship between some anthropometric indices and environmental factors with the development of fine and gross motor skills in preschool children that aged 3-6 in north of Tehran,2014.

Materials & Methods: The research society was Tehran’s first and second areas preschools. Four preschools were selected based on availability and 206 children (girls and boys) participated voluntary. Data were collected from the family information questionnaires and Denver development test type 2.

Results: On average, only 56/06 percent of children in gross motor skills and 77/56 percent of children in fine motor skills were in normal and developed conditions. But 23/86 percent of children in gross motor skills and 14/9 percent of children in fine motor skills were at caution and 12/83 percent of children in gross motor skills and 7/56 percent of children in fine motor skills were exposed to delayed development delays in performance. There was a significant correlation among some of the anthropometric indices such as shoulder, hip and arm length, waist, chest circumference and the performance of some gross motor skills such as jumping, hoping, throwing. Among environmental factors, factors like watching television time and sleeping time affected children's kicking.

Conclusion: A noticeable number of children who participated in this study had poor gross motor skills, thus strengthening and improving these skills required to specific attention and planning.

Objective: The aim of the study was to compare the motor skills and the body balance in children with special disorders (Intellectual disability (ID), autism and learning disorder (LD)) with normally children (NC).

Materials & Methods: The present study was a descriptive-comparative (cross- sectional) research, about 120 children including 30 NC, 30 children LD, 30 children with autism and 30 with ID. The mean age of 7.7, selected through the schools and centers for children with special needs Mashhad through staged clustered random selection. To measure the motor skills of the children, 3 gross and fine motor skills measurement scales and body balance skill measurement were used. Descriptive and analytical statistics such as mean, standard deviation and multivariable variance was mainly used

Results: there was a meaningful difference in the gross and fine motor skills and body balance skill, (P<0.0001), between the NC and ID, autism and children with LD. Also among children whit special needs, children with LD earned the maximum points in all of the skills and autism children earned the minimum points.

Conclusion: According to the findings of the study, motor skills and body balance of children with learning disorder, autism and Intellectual disability is weaker than normally children’s. This indicates the need for increased education of children with special needs in this area is at a younger age.