Summary: We study the following singular eigenvalue problem for a higher-orer fractional differential equation
where , , , , for , and , , , , ,
is the standard Riemann-Liouville derivative, and is continuous. Firstly, we give the Green function and its properties. Then we established an eigenvalue interval for the existence of positive solutions from Schauder’s fixed point theorem and the lower and upper solutions method. The interesting point of this paper is that may be singular at , for .