Writing disorder is one of the most common learning disorders among the primary-school students and has covered 30 percent of all the learning disorders. The purpose of the present study is to design the multimedia instructive package with the emphasis on the fundamental skills of learning to write and investigate its effectiveness on the reduction of writing disorders’ symptoms. Method This research is considered as semi -experimental, with pretest- posttest design and a control group. Its population consists of all the male students of third grade in Bijar city in the academic year of 2012-2013. After considering the necessary factors to be included in the research, 30 students were chosen by available sampling method and were randomly assigned into two experimental and control groups. The instruments applied in this research were wechsler intelligence Test, the researcher-made writing Test, the multimedia instructive package, and homework. Data analysis was done using PASW19 software and covariance analysis test. The results of this study showed that the multimedia instructive program has significantly decreased the writing problems of those students affected by this learning disorder through improving visual comprehension skills, visual sequenceing, memory, and distinction (p>0.01). With regard to the effectiveness of this software, it is suggested that in order to decrease the students’ write problems in classrooms, new instructive methods for improving the aforementioned skills be used.