Objective To explore the effectiveness of a new kind of embolization agent-sodium alginate(KMG), and to evaluate the clinical value of 2D color Dopper ultrasound in assessing the therapeutic effect of uterin arterial embolization (UAE) in leiomyomas. Methods Forty nine patients with symptomatic leiomyomas were undertaken UAE with KMG for the treatment. Sonography was performed at 3 ～ 7 days before and,1,3,6 months after UAE with 2D color Doppler for evaluating the 2D echograms and hemodymamics. Results Forty nine leiomyomas were studied after UAE,showing a marked reduction in the size(35% - 90%). No blood flow was demonstrated in the leiomyomas either 3 - 7 days or 1 month or 3 months after the procedurc. The reappearance of blood flow could be seen in only one case. Conclusion KMG is an efficient embolization agent for the treatment of symptomatic leiomyomas with UAE,and ultrasonography is a useful tool to assess the effectiveness. (J Intervent Radiol, 2006, 15: 469-471)