A sports therapy program in type 2 diabetes helps in glucose control, but little is known how a long-term structured exercise intervention affects the parameters in this disease. Our aim was to measure the impact of a 24-week-long sports therapy program in type 2 diabetes on the concentration of glucose in blood, body composition, and physical fitness level. In this prospective longitudinal study, 208 type II diabetic patient (80 male, 128 female, aged: 61±6.86 years) were selected and randomly assigned to a control or an intervention group. The intervention group took part in a sports therapy and recreation sports program for 6 months. Taking into account the rules of training theory and physiotherapy, fitness material of exercising (aerobics, resistance training, muscle strengthening, stretching) and outdoor elements were used during the 3-month sports program, after which it became a 3-month recreation exercise program. In the control group, there was no intervention. The intervention group showed significant decrease in concentration of glucose in blood (mean differences [MD]:-3.23; Confidence Interval [CI] lowest: -3.50; CI highest: -2.95]; P<0.01), weight (MD: -1.68; [-0.82, -0.52] P=0.01), BMI (MD: -0.37; [-0.82; 0.08]; P=0.01), body fat percentage (MD:-1.74; [-2.15, -1.34]; P=0.05) and visceral fat (MD:-0.37; [-0.67, -0.07; P=0.01); right (MD: 5.33; [4.98, 5.68]; P<0.01) and left arm curl (MD: 5.23; [4.87, 5.60]; P<0.01) test, chair stand test (MD: 2.95; [2.65, 3.25]; P=0.00) and the 6-minute walk test (MD: 111.21; [101.12; 121.31]; P<0.01) showed significant improvement. A 24-week-long sports therapy program is a successful intervention for improving parameters affected by type 2 diabetes.