Field experiment was conducted to find out the cause of calcium deficiency of burley tobacco (Nicotiana tabacum L.), Liming materials and application rate were CaSO4 : Ca 35kg/10a, CaCO3 : 35kg/10a and agricultural lime : Ca 142kg/10a. The breakdown in tissues at tips and margins of upper leaves was developed at maximum growth stage. If complete breakdown and death does not occur and growth takes place later, giving the leaf a scalloped appearance. Upper leaves contained lower calcium content than other leaves. The stem and midvein of calcium deficient plants contained lower calcium and calcium minus oxalic acid, but higher oxalic acid contents than those of normal plant. Fresh leaves of limed plot contained higher calcium and oxalic acid, but not significant increment of calcium minus oxalic acid than those of unlimed plot. Since calcium oxalate is insoluble, it could precipitate within the culls if the calcium and oxalic acid are accessible to each other. It suggest that high level of oxalic acid in stem and midvein could be interfering with translocation of calcium to upper leaves.