This study explored the effects of noticing and computerized dynamic assessment on the learning of Persian vocabulary through reading. In this quasi-experimental study, 75 intermediate learners of Persian as a Foreign Language (PFL) were assigned to three equal-sized groups. In the Noticing and Computerized Dynamic Assessment (CDA) groups, the learners were notified that there were highlighted unfamiliar words in the texts and they were required to infer their meanings by the help of their own knowledge and textual and contextual clues. In the CDA group, struggling learners received mediational hints through a software program which helped them to infer word meanings successfully. In the control group, the learners were not notified of unfamiliar words and they were not required to infer word meanings. It took four days to administer the four treatment texts. One day before the first treatment session, the pretest of unfamiliar words was given. One and thirty days after the last treatment session, vocabulary learning and retention posttests were administered. On learning and retention variables, the Noticing group's mean was significantly higher than the control group's; and the CDA group's mean was significantly higher than the control and Noticing groups' means. The results indicated that noticing of texts' unfamiliar words and adoption of dynamic approach to assessment through the CDA software enhanced vocabulary learning from reading.