Abstract This study aims at revealing the efficiency of using problem-solving strategy in the development of creative thinking and academic achievement for grade eight in the sultanate of Oman. The study population consists of 2814 students of grade eight students in the public schools for basic education in South-Btinah governorate for the academic year of 2015-2016. The study sample consists of 64 students of grade eight in Aqeel Bin Abi Talib school for basic education. To achieve the study aims, the researcher used Torrance test A & B. The researcher also designed a unit following problem-solving strategy and then created an exam on that unit. The credibility of this study tools was measured by presenting it to examiners to identify the external of the first tool (Torrance Test), and the content reliability in regards to the unit mentioned previously. The reliability of the tools was measured by the internal harmony of it using Cronbach equation that is applied on both of Torrance test and the exam. findings of the study is that there are differences of statistical among the experimental groups pertaining the dimensional measurement of the total grades of Torrance test and its different levels in favor of experimental group. That is a result of using the independent variable (Problem-solving). The study also finds differences of statistical among the experimental groups for both pre and post measurements and in the arithmetic average of fluency, flexibility and originality in favor of the post application of Torrance test. Considering the previous findings, the study recommends that some of the course content should be reformulated and restructured in a way that suits problem-solving strategy. The study also recommends the inclusion of problems and situations that challenge the students' mental abilities.