Lysine intake during gestation has a major impact on subsequent reproductive performance. The objective of this experiment was to determine the effect of lysine intake from mid-gestation until farrowing on the reproductive performance of multiparous sows. On day 30 of gestation, 200 Landrace${ imes}$Large White sows were randomly assigned to one of four groups based on body weight and parity (n = 50). The gestation diets contained 0.46, 0.56, 0.65 or 0.74% lysine. Increasing dietary lysine concentration improved sow body condition at farrowing and increased litter weights (p<0.05). Dietary lysine level also had a significant effect on the dry matter (p<0.05) and protein content (p<0.05) of colostrum. Increased lysine intake increased serum insulin concentration (p<0.05) and there was a trend towards increased serum prolactin content (linear, p = 0.07). However, increased lysine tended to decrease blood urea N (quadratic, p = 0.05). These results suggest that higher lysine levels (0.65-0.75%) than those recommended by the National Research Council improved reproductive performance for multiparous gestating sows and this increase may be partially mediated through blood metabolites or metabolic hormone levels.