The purpose of this study was to investigate the Omani EFL learners' writing self-efficacy beliefs in relation to their writing abilities. The study also identified the influence of students' level of English, gender and stream in their writing self efficacy beliefs and writing abilities. The instruments used to conduct this study were a writing test and a writing self-efficacy scale. The writing test was used to determine the Omani EFL learners' writing abilities and the scale was used to identify the self-efficacy beliefs that learners hold about their writing, The sample of the study included 1000 students enrolled at the Language Center at Sultan Qaboos University in the year 2003/2004. They included 429 females and 571 males; 842 were in the Science stream, whereas 158 were in the Arts stream The results have shown a highly significant relationship between the Omani EFL learners' writing self-efficacy beliefs and their writing abilities. Their beliefs about writing were found to be influenced by their level of English, their gender and stream. However, the learners' writing abilities were found to be influenced only by the level of their English and gender. In general, the higher the students' writing self-efficacy beliefs, the higher their writing abilities were found to be.