Introduction: In recent years, children have faced limitations in their playing surrounding, that can affect their cognitive operation. Aim: The purpose of the present study was to investigate the effect of all types of attitudes into the outdoor playings on childrens cognitive flexibility during Covid-19 home quarantine. Method: This paper was a cross-sectional observational study. A total of three hundred female students by the mean age of the 9 to 11 were participated in this study voluntarily by sampling method. Participants were selected from a school in Tehrans 19th district in 2020-2021 academic year. An online survey using a structural questionnaire createing by Google forms were used for data collecting. The online questionnaire consisted of three sections: demographic information, Childrens Cognitive Flexibility, and Parents Attitudes into the outdoor and playings and playing in nature. Variance analysing were used to analyze the data and Tukey's post hoc test were used to Locate the differences. SPSS25 were used for data analysing. Results: The analysis of variance resulted in a significant difference between the mean cognitive flexibility of those children whose parents had a positive attitude towards playing in nature compared to a negative attitude towards playing in nature (p=0.001). The results showed a better cognitive flexibility in those children whose parents had a positive attitude towards playing in nature. Conclusion: Positive or negative attitude of parents towards outdoor playings has an effect on childrens cognitive flexibility during home quarantine.