The experiment was conducted at Tuber Crops Research Sub-Centre (TCRSC), BARI, Bogra during 2002 and 2003 cropping seasons. The experimental site of Bogra was high land and the soil was sandy loam in texture. The pH value of the soil was within the range of 5.5 to 6.2. The experimental plot was well ploughed. Recommended doses of fertilizers and manure suggested by TCRC, BARI, Gazipur were used. Cowdung was incorporated in the soil during land preparation at the rate of 10 t/ha. Urea, Triple super phosphate (TSP), Muriate of potash (MP), Gypsum, Zinc sulphate and Boric acid were used respectively, at the rate of 325, 220, 250, 120 14 and 6 kg per hectare. Urea TSP, MP, Gypsum, Zinc sulphate and boric acid were the sources of N, P, K, Ca, Zn and B, respectively. In both the seasons seeds of potato variety, Diamant were used. Seed tubers were collected from Breeders Seed Production Centre (BSPC), BARI, Debigonj, Panchagarh. The experiments were laid out in a Randomized complete Block Design (RCBD) with three replications. The unit plot size was 3.0 × 3.0 m. Spacing of row to row (within plot) and tuber to tuber (within row) was 60 cm and 25 cm, respectively. Each plot had five rows and in each row 12 seed tubers were sown. Two times weeding was done at an interval of 30 days. Earthing up was executed two times throughout the entire growing period, one at 30 days and another one at 60 days after planting. Irrigation was scheduled two times just after earthing up. Proper control measures were taken to control insect pest (cut worm and aphid). Dursban (0.5%) and Metasystox (0.1%) was applied respectively, to control cut worm and aphid. Thirteen fungicides were included to determine their effectiveness against late blight. There were 12 treatments in both the crop seasons consisting of 11 fungicides and one control. In 2002, the treatments were: Amcozeb, Coromil Mz-72 WP, Dithane M-45, Filthane M-45, Mancozeb, Metaril, Melody Duo, Oxivit, Unilax, Vitamyl Mz-72, Zhemetalax and control. All the fungicides were used at 0.2% that means 2g of fungicides per 1000 ml of water. In 2003 crop season the treatments were: Amcozeb, Filthate M-45, Mancozeb, Metaril, Melody Duo, Oxivit 50 WP, Ridomil Gold, Secure, Unilax, Vitamyl Mz-72, Zhemetalax and control. All the fungicides except Secure were used at 0.2% while 0.1% used in case of Secure. In control treatment, equal amount of plain water was sprayed. Except Dithane M-45, all the fungicides were new ones, had been introduced in the country for registration. Fungicidal solutions were prepared by dissolving definite amount of the chemicals in definite quantity of plain water. Spray was initiated just after the detection of late blight symptoms in the experimental area and repeated thrice at an interval of 10 days. Care was taken during spray both the upper and lower surface of leaves as well as stems was well covered by fungicidal solution. Spray tank was thoroughly washed before filling fungicidal solution materials. Data were taken on foliage infection, disease severity (1-9 scale), PDI (Percent Disease Index) and yield. After harvesting tuber yield per hectare was computed based on total tuber yield per plot. The crops were harvested March 6, 2002 and February 25, 2003 for 2002 and 2003 crop season, respectively. Whenever necessary data were transformed following Arcsine transformation method. Means were compared following Duncan's Multiple Range Test (DMRT).