Simultaneous dual hepatic vein embolization (DHVE) has been proposed for safe right-sided hepatectomy, with good results for liver hypertrophy and function. However, the histological and radiological findings of DHVE have not been thoroughly investigated. This study included 14 patients who underwent DHVE before right-sided major hepatectomy. DHVE was performed if the future liver remnant was < 35% or borderline, but with concomitant vascular resection. The liver function was assessed using the signal intensity on Gd-EOB-DTPA-MRI. A histological evaluation of the area of DHVE and portal vein embolization (PVE) were performed. The median pre- and post-functional liver remnants were 363ml and 498ml, respectively (p < 0.001). The median growth rate was 48.6%, and there was no post-hepatectomy liver failure in the patients who underwent DHVE. The signal intensity ratio in the area of DHVE was lower than that in the areas of PVE and the remnant liver (p < 0.01). The degree of congestion and necrosis was greater in the area of DHVE than in the area of PVE alone (p < 0.01 and p = 0.04, respectively). We observed good liver hypertrophy after DHVE and histological and radiological changes in the area of DHVE. Our findings provide a compelling rationale for further investigation of the mechanism of liver hypertrophy in DHVE.