The hot spot on liver scan was demonstrated by many authors in various conditions such as SVC obstruction, Budd-Chiari syndrome, liver abscess, hemangioma of liver, hepatic venoocclusive diseases, IVC obstruction, and tricuspid insufficiency. And the appearance of hot spot in SVC obstruction is due to unsual collateral circulation. But there was no report of this hots pot on liver scan in our country. We have recently observed one patient with SVC obstruction who shows well-defined area of increased radioactivity between right and left lobe of liver on liver scan using $^{99m}Tc-tin$ colloid, and demonstrated collateral circulations with RI venography using $^{99m}Tc-O_4$. The injection site of radiocolloid was left antecubital vein. This hot spot did not appear when the radiocolloid was injected into right leg vein. We report here this hot spot on liver scan in SVC obstruction with review of some liter atures.