In this paper, we study the periodic problem for the Liénard equation with an indefinite singularity of attractive typewhere f : (0, +∞) → R is continuous and may have singularities at zero, r, ϕ : R → R are T-periodic functions, and μ is a positive constant. Using the method of upper and lower functions, we obtain some new results on the existence of positive periodic solutions to the equation.