The particle size distribution and physical stability of commercial lipid emulsion inject, $intralipos^R$ before and after mixture with total parenteral nutrition(TPN) was tested. Three TNAs were prepared by adding intralipos to P-TPN, Neo-TPN and IVH-2 respectively. Particle size of fat emulsion in three TNA preparations were measured by using LPA-3000 photon correlater. Each TNAs was stored for 48 hours at $4^{circ}C;and;25^{circ}C.$ During storage, three TNAs showed the particle size in the range of 40-1000nm(about $100\%$ of total fat) and in the range of 1000-8000nm(less than $0.005\%$ of total fat). All TNAs were stable in terms of pH and visual appearance. The results showed that added lipid emulsion was stable for 48 hours at $4^{circ}C;and;25^{circ}C$.