Researchers' findings have already reached a general consensus that teacher planning has a significant effect on both teaching and learning. Many studies have been carried out to investigate effective ways to construct and improve planning However, few studies have been done in a cultural context to help understand the similar and different challenges in teacher planning. A mixed methods study design was employed to determine what differences in teachers' lesson planning exist between two groups of teachers worked in different two regions. This study examines teachers (N=81) at the primary level from two regions in the United States and two regions in Turkey participated. Their demographics and data regarding the amount of time worked each week, the time on planning each week and opinions on the nature of planning were investigated. The findings of the study revealed differences in the cultural perspectives of the American and Turkish teachers in planning The different challenges that teachers faced brought into light new possible efforts to help teachers improve their teaching.