Background: primary and secondary education play important roles in promoting educational equity. However, under the influence of multiple complex factors, educational equity is difficult to be effectively guaranteed. Significance: the investigation and analysis of the current situation and causes of educational equity in primary and secondary schools can help to allocate educational resources more rationally, optimize educational financial investment, and reduce educational inequity. Motivation: countermeasures and suggestions are put forward through th analysis of the the current situation and causes of educational inequity in Linyi City. Data: teachers and students from 10 primary and middle schools in 5 districts and counties of Linyi City were selected as the survey objects, and the basic information of schools and families, school resources, and students' academic performance were collected. Methods: analysis of variance (ANOVA) and regression analysis were used to explore the impact of educational resource differences on students' academic performance. Results: there were significant differences in students' academic performance under different family conditions, learning conditions, extracurricular tutoring intensity, teachers' teaching ability, and school facilities (p<0.01). The family conditions, learning conditions and teachers' teaching ability had significant effects on the learning performance of primary and secondary school students in Linyi city, and whether the school was located in the city center and the edge of the city also had significant effects on the students' learning performance. Conclusion: differences in family conditions and extra-curricular tutoring intensity lead to educational inequity to a certain extent, and school educational resources partially guarantee educational equity. Suggestions: the countermeasures to solve the inequity of education should be put forward from the aspects of building learning environment and atmosphere, reducing after-school burden and promoting quality education in non-central urban areas.