It is generally considered that Myleran in high dosage is very toxic. Therefore clinicians treat CGL conventionally with continuous low doses of Myleran. The authors treated 15 previously untreated and 11 recurrent cases with intermittent high doses of Myleran. The result is satisfactory with following advantages: prompt alleviation of symptoms, shorter time to induce remission, rare severe suppression of bone marrow and simplicity for use, hence it might be the better method to treat CGL.