This paper deals with the study on the thermooxidative degradation reaction and its kinetics of the medical rubber latex tube sample made from PPVL (peroxide prevulcanized natural rubber latex) in air atmosphere with the temperature rising rates (B) 5 oC/min, 10 oC/min, 15 oC/min, 20 oC/min, 25 oC/min and 30 oC/min with TGA method. The results of TG and DTG curves show that the oxidative degradation of the sample is a two-stage reaction. The temperature at 1;weight loss Too1, the degradation peak temperature Tp and the final temperature Tf shift towards high temperature side with the increment of B and the degradation rate increases at the same time. The features of these curves with 6 different B are similar. The sample shows obviously by an oxidative weight gain peak rises with the increment of B, but the weight gain rate decreases; the peak temperature of weight gain is 187.9 oC and the weight gain rate is 1.33;when the temperature rising rate B of the test sample is 5 oC/min; the maximum rate of thermooxidative degradation (Cpl), the final rate of thermooxidative degradation (Cfl) and the activation energy of reaction (E) increase also with the increment of B; the apparent activation energy Eo is 107.5 kJ/mol, the degradation reaction order (n) is 1.7, they are not influenced by B. Cp2 and Cf at the second stage are not affected by B virtually; n varies with different B, but no correlation exists between them; E increases as B rises, Eo = 154.0 kJ/mol. THe frequency factor (A) in the first and second reaction stage increases as B rises, the increment appears almost as geometric progression. The maximum correlation coefficients r in the first and second stages of reaction are above 0.999 and 0.982 respectively. The degradation rate at 600 oC of that samples with various temperature rising rate is from 99.2;to 99.5;.