Increase rates of erythrocytes and of heomoglobine of the rabbit's femur bone marrow on every 3rd., 5th, 10th, 20th, 30th and 60th days affer the unilateral Iumbar sympa the ctomy in fluid medium culture were examined. The results obtained were as follows:- (1) The maximum increase rate of erythrocytes did not occur till 5th or 10th day after the denervation, and the value fell progressively till 60th day. (2) The rate of hemoglobine showed its maximum on the 3rd. or 5th day after the operation, then decreased till both day, in which showed very little differences between both sides. (3) In most cases, increase rates of erythrocytes and of hemoglobine did not exceed over 20 percents. In concusion. the sympathetic denervation promotes the function of rabbit's bone marrow, but it only lasts a short while. This may have been due to the inerease of blood flow in the bone marrow, and secondarily it caused the hyperfunction of the bone marrow.