BACKGROUND Test anxiety often leads to poor academic performance. This study aimed to determine the effect of computer-based tests on nursing students' test anxiety. METHODS This quasi-experimental study was conducted in 2016 on 39 nursing student with anxiety score under 128 on Spielberger's State-Trait Inventory (STAI). They were randomly allocated to computer-based tests (CBT) and paper-based test (PBT) group. Prior to exam, all students completed Sarason's Test Anxiety Scale (TAS). We administered CBT for students in experimental group. Data were analyzed using independent t-test and one-way ANOVA. RESULTS Students mean test anxiety score was 11.94 and 11.32 in CBT and PBT groups, respectively. 47.4% of students in CBT group and 29.4% of those in PBT group experienced higher test anxiety, while the difference was not significant (p=0.56). CONCLUSIONS Despite, there was no significant difference between anxiety score of two groups; but students' test anxiety score was higher in CBT group. With the current increase in computer-based assessment, educational administrators must be aware of and plan for the possible unfavorable effects of computer assisted testing, such an anxiety. Future studies are needed to evaluate and compare the effect of different type of student testing such as distance testing or CBTs using new information technologies such as laptop, tablet or mobile phone on students' test anxiety and performance.