This study evaluated the impact of level and solubility of dietary fiber on sow and litter performance when fed during the pre-farrowing period. Sows (n=82) were assigned by BW to a 2×2 factorial arrangement plus a control treatment (regular lactation diet; 11.30% TDF) with the following factors: 1) High soluble dietary fiber (SDF; 6.0%) and insoluble dietary fiber (IDF; 31.10%); low soluble dietary fiber levels (SDF; 4.2%) and insoluble dietary fiber levels (IDF 28.30%) and 2) supplementation level of a fiber top-dress added to the lactation feed (0.45 vs 0.90 kg). The top-dress supplements were formulated to meet target fiber levels using sugar beet pulp and wheat middlings. Sows were transferred into the farrowing house at approximately 113 (±1d) days of gestation and experimental treatments were implemented from placement until parturition. Fiber solubility and top-dress level had no effects on sow BW during the pre-farrowing period and lactation (P >0.05). Lactation length was unaffected by treatments (P=0.57). Piglet birth weight (P=0.35), stillborn pigs (P=0.76), and number of pigs born below 0.90 kg (P=0.89) did not differ between treatments. Wean weight of piglets was not different between treatments (P=0.84) but, insoluble fiber increased (P=0.04) the number of small weaned pigs (less than 3.6 kg BW) irrespective of supplementation level (2.23 vs 1.10, and 0.37, for insoluble fiber, control, and soluble fiber, respectively).