This study aimed to determine certain biochemical and reproductive parameters in cyclic and acyclic Holstein cows at the end of the voluntary waiting period. A total of 30 Holstein cows, were used in the study. Among these animals, those with a corpus luteum (CL) on their ovaries in either of the consecutive examinations performed on days 45 and 55 postpartum, and had a blood progesterone level >1 ng/mL, were considered cyclic (n=15); Those with no CL on their ovaries in either examination and with a blood progesterone level <1 ng/mL were considered acyclic (n=15). On day 55 postpartum, blood samples were obtained from each cow. Parity and body condition score (BCS) were recorded for each animal. The serum samples were collected and stored at –80°C until analysis. β-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA), glucose, cholesterol, triglyceride and progesterone levels were measured. The first estrus after the voluntary waiting period was determined based on increased locomotor activity, uterine tone, and the presence of a Graafian follicle on the ovary. Farm records were used to evaluate the reproductive parameters. It was found that the intervals from calving to first estrus, calving to first insemination, and calving to conception were significantly shorter in cyclic cows compared to acyclic cows. When comparing biochemical parameters, parity, and BCS, no significant differences were found between the groups. In conclusion, while there were no significant differences in biochemical parameters, parity, or BCS between cyclic and acyclic cows, reproductive parameters were significantly improved in cyclic cows.