The presented article proposes to pay attention to the existing functional features of voice category in Kazakh language and consider their functions in sentences. The methodological part of the article sets out the opinions and reasoning of domestic and Russian linguistic scholars about the voice categories and functional grammar. The categories of voice proposed by the great scientist Akhmet Baytursynuly who made a great contribution to the grammar of Kazakh language. Those categories are analyzed and their functional properties are determined. When disclosing the value of the voice category the importance of the aspectual, temporal, causal and modal fields of functional grammar is considered. In Kazakh language active voice will be compared to the analogical types of voices in Russian and English languages. The importance of active voice that was proposed by Akhmet Baytursynuly will be determined through examples and the need for its re-introduction into the practical textbooks of Kazakh language is also offered. To create the possibility of full disclosure of values of the first ten voices approved by Akhmet Baytursynuly needed to be provided for their detailed analysis on the basis of aspectual, temporal, causal and modal functional categories. Also giving reliable research findings, the article recommends contributing them to be re-included into Kazakh language grammar