This study aims at investigating the effectiveness of using Mind Map strategy in teaching social studies on the achievement of Ninth-Grade Students and their attitudes about it. The sample consisted of 60 ninth-grade female students from Zineb AL-Thaqafia Basic Education School (6-10) in Muscat. The sample was divided into two groups: an experimental group taught by Mind Map and it consisted of 30 students, and a control group taught by the usual conventional method and it was consisted of 30 students. The experiment took four weeks. To achieve the goals of the study, the researcher prepared two instruments: an achievement test and an attitude scale. The former consists of 30 items classified under three question types: multiple-choice, completion and short essays. The questions covered three cognitive levels, which were: knowledge, comprehension and application. The latter instrument consisted of (31) statements. The validity of the two instruments was established via a panel of expert judges. Reliability of internal consistency of the each instrument was assessed using the Cronbach-Alpha method. The achievement test and the attitude scales were found to be reliable instruments (0.80 and 0.89) respectively. The findings suggest that there are statistically significant differences among the means of the student's performances of the two groups at the significance level (0.05) in the overall achievement test and among the cognitive levels in favor of the experimental group. The findings also show that there are positive attitudes towards using the Mind Map strategy of teaching social studies. Based on the findings the researcher recommends running seminars and workshops for teachers and supervisors in the Teaching Social Studies field to raise awareness about the effectiveness of using the Mind Map Strategy. Furthermore, it is recommended to encourage teachers of Social Studies to use it as a teaching, learning and evaluation tool. The study also recommends conducting further similar studies with different learners' levels.