Objectives This study aimed to identify Internet use and risky online activities in children with developmental disorders from the viewpoint of parents. Methods This descriptive study was carried out with the parents of 407 children, aged between 6 and 17, who were receiving educational and rehabilitation support at the special education and rehabilitation centers. A questionnaire consisting of socio-demographic data and information on risky online activities was used to collect data. Results Mobile phones are the preferred device for 89.1% of children to access the Internet. The average age for starting to use a smartphone is 4.57 ± 2.10 years. Most commonly, children use the Internet for playing games (86.5%), listening to music (73.9%), and watching videos (69%). Risky online activities were noted while using the Internet, including revealing actual names (69.8%), submitting personal photos (90.6%), sharing personal photos with others (93.8%), and divulging the streets of their neighborhood (46.1%). Conclusions Internet practices of children with developmental disorders are precarious. Thus, it is crucial for parents to assume substantial responsibility in safeguarding children with developmental disorders from risky online activities. Educational programs should be developed to raise awareness and encourage responsible use of the Internet in order to promote healthy digital literacy.