该文运用Banach压缩映射原理和Schaefer不动点定理研究星图上的非线性分数阶微分方程边值问题 $ \left\{\begin{array}{ll}{}_{C}D_{0,x}^{\alpha}u_{i}(x)=f_{i}(x,u_{i}(x),\ {}_{C}D_{0,x}^{\beta}u_{i}(x)),0<x<l_{i},&i=1,2,\cdots,k,\\u_{i}'(0)=u_{i}(1)=0,&i=1,2,\cdots,k,\\u_{i}''(l_{i})=u_{j}''(l_{j}),& i,j=1,2,\cdots,k,i\neq j,\\ \sum\limits_{i=1}^ku_{i}''(l_{i})=0,& i=1,2,\cdots,k \end{array}\right. $ 解的存在唯一性,其中$ 2<\alpha\leq3,0<\beta<1,$ ${}_{C}D_{0,x}^{\alpha},$ ${}_{C}D_{0,x}^{\beta} $是Caputo分数阶导数,$f_{i},i=1,2,\cdots,k$是$[0,1]\times R\times R $上关于三个变元连续可微的函数.