This work it is a qualitative action research, which involved the development of a preparatory course for Celpe-Bras' Oral Part in an online context, its realization and the investigation of its contributions and limitations for the development of Spanish-speaking students' oral proficiency and for the preparation for the oral part of the exam. The aim was to promote a course that focused on Celpe-Bras, that did not sum up to mere presentation tips on how to get a good score on the test, but a course that would provide effective opportunities for oral proficiency gains, having as theoretical assumptions the communicative approach in language teaching and assessment as an integrating element in the teaching and learning processes. The need for this research was identified due to the shortage of Celpe-Bras specialized courses and because of the difficulty to find long distance Portuguese courses for foreigners that offer opportunities for oral practice. The present work was based on theories about oral proficiency assessment, as well as theories about course planning and the use of technologies in education, specifically in foreign language teaching (FL). The questions that guided this research were: (1) What are the contributions of the use of communicative tasks (CTs) in the preparation for the Oral Part of Celpe-Bras in an online context?; (2) What similarities and differences can be found between the tasks and synchronous simulations proposed in the course and the oral interaction of Celpe-Bras, in relation to (a) subjects and (b) communicative functions?; (3) How did the proposed course contribute to gains in the oral performance of Portuguese learners in an online context, considering Celpe-Bras' criteria for oral evaluation? For the execution of this research, three Spanish-speaking participants, who initially presented the intermediate level of oral proficiency in Portuguese and proved able to cope well with technological tools, were selected. The results indicate that the use of CTs in the proposed course contributed to the development of the participants' oral proficiency oas well as to the preparation for Celpe-Bras. In addition, the data indicate that the proposed activities promoted effective opportunities for the students' oral practice and development of the students.