The existence and uniqueness of positive solution is obtained for the singular second-order m -point boundary value problem u ′′ ( t ) + f ( t , u ( t ) ) = 0 for t ∈ ( 0,1 ) , u ( 0 ) = 0 , u ( 1 ) = ∑ i = 1 m - 2 α i u ( η i ) , where m ≥ 3 , α i > 0  ( i = 1,2 , … , m - 2 ) , 0 < η 1 < η 2 < ⋯ < η m - 2 < 1 are constants, and f ( t , u ) can have singularities for t = 0 and/or t = 1 and for u = 0 . The main tool is the perturbation technique and Schauder fixed point theorem.