Circadian rhythms of hemocoagulations and platelet aggregation were determined in chronics with pyelonephritis suffering from or free of renal dysfunction. Chronostructure of relevant circadian rhythms was recorded before and after 3-week combined chronotherapy with heparin and curantil. The readings were taken 6 times a day. The results obtained at group-mean and individual cosinor analysis showed disorganization of circadian rhythms of hemostasis in the above patients. Combined heparin and curantil chronotherapy corrected the above defects. Normalization occurred on the treatment day 26.