The present study explored the effectiveness of web-based distance (online) inservice training for basic education (Cycle One) EFL teachers in Oman. It also investigated the effect of distance training on teachers' performance and attitudes towards an online training as well as the difficulties that teachers encounter when joining such online training, This is an experimental study of Pretest-Posttest-control group design. It compared the effect of two inservice training format-online and face-to-face- on teachers' performance and attitudes towards online training. Sixty Basic Education (Cycle One) EFL teachers who were recruited in Dhofar Region for the academic year 2007-2008 included in this study. They were divided into two groups: Thirty (30) EFL basic teachers were randomly assigned for the experimental group and the other thirty (30) teachers were assigned to the control group. The designed training programme for primary English teachers (PRIT) was given to teachers on a platform of moodle. The control group received face-to-face training in a regular training centre, and the experimental group trained through a web-based on-line course. Both groups were using the same training materials which are " - In-service Course for Basic Education (Cycle One) English Specialists "PRIT".: The data analysis in this study found that participants who received online training had a significant difference (The Experimental group which was training electronically reported a significantly higher level of performance with mean scores of 78.16, T-value was 3.13 that was significant (p=.003) at 0.05 level, whereas the control group that was trained by face-to-face training obtained mean scores of 71.56) in perceived learner achievement when pretest to posttest mean gain scores were measured. This led the researcher to the conclusion that the method of training does have significant effect on teachers achievement and attitude. There was also statistical significance regarding improvement of teachers' attitudes from pre to post testing. Significant differences were found in favor of the experimental group.