The problems associated with the development of the petrochemical industry of the Republic of Kazakhstan are investigated by creating a petrochemical cluster in the western oil and gas region of the country. The issues of a forming petrochemical cluster in Kazakhstan and creating an integrated petrochemical complex in Atyrau region are considered. The essence of the cluster approach as the main factor for increasing the regional competitiveness of the Atyrau region is opened, the expediency and efficiency of the creation of the petrochemical cluster and an integrated petrochemical complex is substantiated. The stages of construction of an integrated petrochemical complex are described, depending on the sources of supply of the used raw materials. An integrated scheme of the petrochemical complex was created and investment petrochemical projects in the Atyrau region were considered. The main groups of factors substantiating the opportunities for the formation of a petrochemical cluster and the achievement of an economic effect in western Kazakhstan are defined.