Our objective was to determine whether abomasal infusions of increasing doses of oleic acid (cis-9 C18:1; OA) improved fatty acid (FA) digestibility and milk production of lactating dairy cows. Eight rumen-cannulated multiparous Holstein cows (138 d in milk ± 52) were randomly assigned to treatment sequence in a replicated 4 × 4 Latin square design with 18-d periods consisting of 7 d of washout and 11 d of infusion. Production and digestibility data were collected during the last 4 d of each infusion period. Treatments were 0, 20, 40, or 60 g/d of OA. We dissolved OA in ethanol before infusions. The infusate solution was divided into 4 equal infusions per day, occurring every 6 h, delivering the daily cis-9 C18:1 for each treatment. Animals received the same diet throughout the study, which contained (percent diet dry matter) 28% neutral detergent fiber, 17% crude protein, 27% starch, and 3.3% FA (including 1.8% FA from a saturated FA supplement containing 32% C16:0 and 52% C18:0). Infusion of OA did not affect intake or digestibility of dry matter and neutral detergent fiber. Increasing OA from 0 to 60 g/d linearly increased the digestibility of total FA (8.40 percentage units), 16-carbon FA (8.30 percentage units), and 18-carbon FA (8.60 percentage units). Therefore, increasing OA linearly increased absorbed total FA (162 g/d), 16-carbon FA (26.0 g/d), and 18-carbon FA (127 g/d). Increasing OA linearly increased milk yield (4.30 kg/d), milk fat yield (0.10 kg/d), milk lactose yield (0.22 kg/d), 3.5% fat-corrected milk (3.90 kg/d), and energy-corrected milk (3.70 kg/d) and tended to increase milk protein yield. Increasing OA did not affect the yield of mixed milk FA but increased yield of preformed milk FA (65.0 g/d) and tended to increase the yield of de novo milk FA. Increasing OA quadratically increased plasma insulin concentration with an increase of 0.18 μg/L at 40 g/d OA, and linearly increased the content of cis-9 C18:1 in plasma triglycerides by 2.82 g/100 g. In conclusion, OA infusion increased FA digestibility and absorption, milk fat yield, and circulating insulin without negatively affecting dry matter intake. In our short-term infusion study, most of the digestion and production measurements responded linearly, indicating that 60 g/d OA was the best dose. Because a quadratic response was not observed, improvements in FA digestibility and production might continue with higher doses of OA, which deserves further attention.