The category of cases is a grammatical category. This is mainly refers to the nouns. The Nouns take a special morphological indicators and fall into different forms, by request of other words and verbs within the sentence. At this time, the morphological indicators, that he has adopted are called case suffixes. The case suffixes are the word-changing suffixes that make connection between words. These suffixes are emphasized and are adjacent to words. The case suffixes of the Noun, as a process that has a very ancient history, has been processed with some phonetic variations at different times. In the modern Turkish and Azerbaijani language, casesuffixes have passed a certain period of time and used with different terms. In the article, we talked widely about it. Although, the case suffixes in Azerbaijani language have stabilized from the last century and reached a certain system. In Turkish this process is slowing down. There are putting forward different ideas and rules around this issue by Turkish researchers. In Azerbaijani, the cases of the Noun are divided into two groups: grammatical and spatial grammatical cases. The category of grammatical case, that dominates spatial images in meaning and content, includes dative case (yonluk hal), locative case (yerlik hal) and ablative case (cixishliq hal). In Turkish these cases are examined. In some cases, these cases are used instead of each other. At this time, the historicity is in the foreground. The study examines the research of both Azerbaijani and Turkish researchers.