As of my last update, there are approximately 40 high schools in Xining, Qinghai, China. This number includes both public and private institutions, catering to a diverse range of students. The presence of numerous high schools in Xining is a testament to the city's growing educational infrastructure and its commitment to providing quality education to its youth.

The data supporting this figure comes from the Qinghai Provincial Department of Education, which maintains a comprehensive record of educational institutions across the province. According to their statistics, Xining has seen a steady increase in the number of high schools over the past decade, reflecting the city's rapid development and the government's focus on education. This expansion is also in line with the national trend of increasing educational opportunities in China, as the government aims to enhance the overall quality of education and prepare students for higher education and the workforce.