This study objective was to investigate the "Relationship between use of Educative Play Materials and cognitive Development of Nursery School Children in Niger State". Four specific objectives with four research questions were stated and three null hypotheses were raised. Among the objectives were to identify different types of Educative play materials in Nursery schools in Minna Educational Zone, Niger state, and to assess the difference in cognitive development among Nursery school children who were exposed to Educative play materials and those that were not: Experimental research design was adopted for the study. The population for the study was 10,152 nursery school children. The sample size for the study was 240 Nursery school children. Sixty (60) children per school were drawn from four private Nursery schools Minna Educational Zone, Niger State. Thirty (30) children, 15 male and 15 female served as experimental group and control group respectively. Two types of instruments were used to collect data. Questionnaires were administered to the proprietors/proprietresses of the four sampled schools. The questionnaire provided information for research question one, while Intelligence (standardized Intelligent Quotient (IQ) test Wechsler Preschool and primary scale of intelligence revised (WPPSIR) modified by the research was the instrument used to collect data from Nursery school children through administration of pre and post tests. The collected data from proprietors of the four sampled schools were statistically analyzed in a tabular form using descriptive statistics such as frequencies and percentages, while data from children were analyzed using one sample t-test to test for the three null hypotheses at 0.05 level of significance. The result on the tested null hypotheses showed P<0.05 for all the null hypotheses at 0.05 level of significance, that (1) There was a significant difference in the cognitive development of nursery school children who used Educative play materials and those who did not (2) There was a significant different in the cognitive development between male and female nursery school children who were exposed to Educative play materials. (3)There was also a significant difference in the cognitive development between urban and rural nursery school children who were exposed to Educative play materials. The study concluded that Educative play materials actually helped in improving children cognitive development and performance when they are effectively utilized for the purpose of teaching and learning. The study recommended that there is the need for schools to invest more in purchasing Educative play materials as it has been found that it could enhance children cognitive development.