The objective of this study was to evaluate the effects of dietary starch content on lactation performance, feed intake, nutrient digestability, nitrogen efficiency, feeding behavior and income over feed cost of Holstein dairy cow in mid-lactation. Four primiparous (DIM = 144 ± 5, milk production = 42.0 ± 3, mean ± SD) and 4 multiparous (DIM = 133.7 ± 4, milk production = 44.7 ± 1, mean ± SD) Holstein cows were used in a 4 × 4 latin square design with 21-d periods. Each period consisted of 16 d of adaptation followed by 5 d of data collection. Different dietary starch were created by replacing corn grain by rice bran. Treatment diets were: high starch (HS), medium starch (MS), intermediate starch (IMS) and low starch (LS). The HS, MS, IMS and LS diets contained 29.9, 27.4, 25.7 and 20.5 % starch (DM % basis), respectively, and were isoenergetic (1.6 Mcal / kgDM). Decreased dietary starch by increase replacing corn grain by rice bran unaffected on the proportion of the particles retained on the two top sieves of the ( 19 mm and 8 mm), but proportion of the particles retained on the 1.18 mm sieve linearly increased ( P 0.01) that caused a linear increase in peNDF 1.18 ( P 0.01). Reducing dietary starch did not affect milk yield, 3.5 % FCM, ECM, SCM, milk energy, and production of fat, protein, lactose, SNF and percentage of fat, while percentage of protein, lactose and SNF were affected by treatments ( P 0.01 ), and decreased linearly by reducing dietary starch ( P 0.05). Decreasing dietary starch, quadratically increased dry matter intake ( P 0.01), and as a result, feed efficiency (MY / DMI, 3.5 % FCM / DMI, ECM / DMI, SCM / DMI) decreased by reducing dietary starch content ( P 0.01). Milk urea nitrogen and rumen ammonia nitrogen increased linearly ( P 0.01) and caused a linear decrease in apparent nitrogen efficiency ( P 0.01). Total-tract digestability of DM and OM redused linearly by reduce starch content of diets ( P 0.01), and total-tract digestabilty of NDF tend to decreas linearly ( P = 0.06). Rumen pH unaffected by treatments while feces pH linearly increased by reducing starch content of diets. Body weight, body condition score and back fat thickness unaffected by treatments. Reduced starch content of diet decreased price of diet (rials / kgDM), but income not affected. Decreased dietary starch increased linearly plasma BHBA and NEFA while plasma glucose not affected by treatments. The results suggest that reduced dietary starch to 27.4 % by replacing part of the corn grain with rice bran, in high concentrate diets can successfully support performance of high producing Holstein cows in mid-lactation. Keywords: Starch, Corn grain, Rice bran, Performance, Dairy cows