This study investigated the effects of the storytelling approach on improving of EFL learners' vocabulary knowledge. To this end, 30 upper-beginner EFL learners (out of a population of 134) were selected by means of an OPT test and were assigned to 2 groups: 1 experimental and 1 group. The participants were selected from among young EFL learners who were between 8 and 14 years old. They had already registered for English classes in Paya Language Center, Isfahan, Iran. As for the materials, they were mainly prepared by the teacher/researcher. Based on the units of "Backpack" books--taught in Paya Language Center--some stories were prepared and adopted by the teacher/researcher along with a visual presentation using the PowerPoint software. In carrying out the study, the participants were taught the key vocabulary via pictures and gestures. Once the participants had identified the new words, the teacher started telling and introducing the stories. While reading the stories, the teacher directed the participants' attention to the PowerPoint presentation that included the visual representation of the story to facilitate the comprehension process. After the treatment, there was a posttest to assess the participants' improvement. Results of data analysis revealed that the storytelling approach to teaching vocabulary proved effective for the experimental group. All the experimental group participants experienced a significantly meaningful increase in their vocabulary knowledge, compared to the control group. Finally, there was a boost in the interest rate of the experimental group participants in terms of motivation.