The aim of this study is to investigate the effect of intensive basketball competitions (10 official basketball games in 12 days intensive competition period) on blood parameters of basketball players. Blood samples were taken from the basketball players of the university team. The players were training regularly and they had no regular health problems. The average age of the players was 22,80 ± 3,20 years and the average height was 185,83 ± 7,57 cm. This study was performed on 10 volunteer basketball players. Blood samples were taken before (24 hours), after (24 hours) and during the intensive competitions. Descriptive statistics (mean and standard deviation) were applied to the data, Wilcoxon two realized sample test was used to compare the values before and after the competition period. When comparing the blood values before and after the competition period, there was significant increase in prevalence of Fe, albumin, AST, ALT, LDL, HDL, MCH, MCHC and the values of UIBC, creatinine, HCT and MPV were significantly low before the competition; (P <0.05). The findings show that the physiological characteristics of basketball players are influenced by intensive competitions. In the literature, the physiological effects of regular and single-session exercises have been investigated in many studies. However, the data about the physiological effects of intensive competition periods are rather limited. A better understanding of these influences will guide the event organizers and coaches to plan the competitions and it will facilitate the preparation of the sportsmen for this intensive competition periods.