One of the most important problem in any statistical analysis is the existence of unexpected observations. Some
observations are not a part of the study and are known as outliers. Studies have shown that the outliers affect to the
performance of statistical standard methods in models and predictions. The point of this work is to provide a couple
of statistical package in R software to identify outliers in circular-circular regression which is written by the author,
we introduce a brief explanation about the circular data and circular regression, then the packages in R for circular
regression introduced. After wand, the functions in the package CircOutlier will be described.