This study describes  working  memory and developing and validating of an  L1 Persian reading span test for the measurement of working  memory of L1 Persian EFL learners. The test, which included  64  Persian  sentences,  was  developed  based  on  Daneman  and Carpenter’s (1980) reading  span  test.  The  shortcomings  of  the  test  were  identified  and  removed  over  three  pilot studies  ...