This study was an attempt to find out the impact of Neuro-linguistic programming (NLP) on EFL learners' writing achievement and critical thinking. To fulfill the purpose of this study, 60 EFL learners of institute in Shahinshahr were selected from among a total number of 100 learners based on their performance on the Preliminary English Test (PET). After homogenizing, they filled out the critical questionnaire developed by Honey (2000) and then they were non-randomly divided into two groups, experimental and control, each consisting of thirty EFL learners. Experimental group members were instructed based on NLP and their instruction was based on five senses (sight, hearing, touch, smell, and taste). The control group members had a routine teaching process in which no NLP methods was imposed in this group. Both groups were female and their age range was between 15-20 years old. After 16 sessions, writing posttest and critical thinking questionnaire were given to two groups to evaluate whether there is any significant difference between these two groups or not. The design of the current study was quasi-experimental posttest only design. The obtained data were analyzed both descriptively and inferentially. For descriptive statistics, mean and standard deviation were obtained and the type of the test applied for this study was independent sample t-test. The statistical analyses revealed that there was significant statistical difference between the two groups’ mean scores on the writing posttest, while there was no significant statistical difference between the two groups’ mean scores on the critical thinking posttest. As a result, it can be argued that NLP had significant impact on learners’ writing skill, but NLP had no significant impact on learners’ critical thinking level. Manuscript profile