The study aims to identify the effect of teaching mathematical problem solving & posing strategies on improving mathematical problem solving & posing skills of grade eight students of basic education. The study tries to answer the following questions: 1- What is the effect of teaching mathematical problem solving and posing on improving grade eight students' abilities to solve mathematical problems? 2- What is the effect of teaching mathematical problem solving and posing on improving grade eight students' abilities to pose mathematical problems? 3- What is the correlation of mathematical problems solving and problem posing on grade eight students of basic education? The study consisted of 63 grade eight students of basic education from Mohammed bin Masoud school (Dakhliya Region). The sample was divided into two groups namely (Experimental and control group). In sake of achieving the study goals, the researcher designed a teaching unit based on pupil's book (Geometry Unit). He applied two exams from his design; one of them is solving mathematical problems and the other is posing problems, The finding of the study revealed the following: - There are statistically significant differences between mean pupils' scores of the two research groups in problem solving exam towards the experimental group. -There are siatistically significance differences between mean pupils' scores of the two research groups in problem posing exam towards the experimental group. - There is a strong positive correlation between the ability of solving mathematical problems and the ability of posing them. The study concluded by giving a number of recommendations to improve student's problem posing and solving skills. These include - Training supervisors and mathematical teachers on using more problem solving strategies and even more significantly, training them on using problem posing strategies. - Applying open mathematical problems in student's book and inserting such problems in mathematics curriculum and syllabus. -Continuing researching problem posing in connection with problem solving or any other variables.