Afan Oromo is the most widely spoken language in Ethiopia. Due to political reasons before 1991 the language was not widely used in writing despite the fact that the Oromo people have long desire to use the language for wider range of functions. Using the privilege that the present government gave to each ethnic language in Ethiopia, Afan Oromo has been serving as an official language in the Oromia regional state since 1991. The language has been serving as medium of instruction in different colleges in Oromia regional state. The language has also got its own Department at BA and MA levels in Universities. For these and other reasons a writing system called ‘Qube'' was developed from Latin script to write the language. However, in Afan Oromo writings like magazines, text books and billboards, different types of errors such as spelling, grammar, punctuation and organization are clearly observed. Among these, spelling and grammar errors are analyzed in this work. Indicating areas of problem in Afan Oromo spelling and grammar, noticeably this work contributes to efforts made by scholars to enhance the proper use of Afan Oromo in writing.