Kidney tumor can cause hypertension, especially about 10%-15% of kidney cancer patients will have hypertension. The causes of hypertension caused by kidney tumor are as follows: 1. The kidney tumor compresses the renal artery, which causes ischemia in the kidney and can lead to hypertension. 2. The arteriovenous fistula formed in the kidney tumor, accompanied by the increase of cardiac output, can also lead to hypertension. 3. For example, renin is produced by kidney cancer to cause hypertension. Clinical studies have shown that among kidney cancer patients with hypertension, the activity of renin in plasma is significantly higher than normal.