Background: Negative attitudes toward stuttering and people who stutter (PWS) are found in various groups of people in many regions. However the results of previous studies examining the influence of fluency coursework and clinical certification on the attitudes of speech-language pathologists (SLPs) toward PWS are equivocal. Furthermore, there have been few empirical studies on the attitudes of Korean SLPs toward stuttering. Aims: To determine whether the attitudes of Korean SLPs and speech-language pathology students toward stuttering would be different according to the status of clinical certification, stuttering coursework completion and clinical practicum in stuttering. Methods & Procedures: Survey data from 37 certified Korean SLPs and 70 undergraduate students majoring in speech-language pathology were analysed. All the participants completed the modified Clinician Attitudes Toward Stuttering (CATS) Inventory. Outcomes & Results: Results showed that the diagnosogenic view was still accepted by many participants. Significant differences were found in seven out of 46 CATS Inventory items according to the certification status. In addition significant differences were also found in three items and one item according to stuttering coursework completion and clinical practicum experience in stuttering, respectively. Conclusions & Implications: Clinical and educational experience appears to have mixed influences on SLPs' and students' attitudes toward stuttering. While SLPs and students may demonstrate more appropriate understanding and knowledge in certain areas of stuttering, they may feel difficulty in their clinical experience, possibly resulting in low self-efficacy.