The present invention relates to liposomal preparation containing irinotecan or irinotecan hydrochloride and preparation thereof. The present liposomal preparation contains irinotecan or irinotecan hydrochloride, neutral phospholipids and cholesterol. A stable liposomal preparation which bearing the characteristics of high entrapment efficiency above 90%, small and narrow particle size distribution, lower toxicity and higher tumor inhibition ratio could be accomplished by controlling the cholesterol and neutral phospholipids weight ratio of 1: 3 to 5.
