Parathyroid hormone (PTH) is the major factor of calcium homeostasis. This hormone increases calcium uptake in intestines through stimulation of the active formation of vitamin D and eventually increases bone density. The aim of this study was to investigate the effect of one session of resistance and endurance activity on PTH and ALP in untrained young girls (mean age 21.9±1.23 yrs, height 161.95±2.7 cm and weight 63.15±6.9 Kg). For this purpose, 30 young female university students (20-25 years old) were selected and divided randomly into three groups: endurance, resistance and control. Exercise protocol in endurance group included running on a treadmill and for 45 minutes with 45% VO2max and in resistance group included front arm, front leg and Scott; each of them were performed in three sets with 55,65,75% of 1RM during 45 minutes. Blood samples were collected in three stages (baseline, 15 minutes and 24 hours after the protocol). The data were analyzed via one-way analysis of variance with repeated measures, and post hoc LSD test at P?0.05. Results showed that the exercise increased PTH and ALP in resistance and endurance group; this increase was slightly higher after resistance exercise than endurance exercise but there was no significant difference between the two groups. The present research showed that one session of resistance and endurance activity significantly increased PTH and ALP in untrained young female.