The aim of the present study was to determine the influence of soil tillage operations and sulphur fertilisation on crop productivity and economic effectiveness of potatoes in East Poland. A two-factor field experiment was realized in Malice, a village near Zamosc (50°42' N, 23°15' E) in 2001–2003 with the method of split-plot in four replications, on leached brown soil formed from coarse sand. 36 plots were marked (with an area of 19.5 m-2) which were meant for potato cultivation, Irga cv. The forecrop for potato was spring Triticale. The experiment considered two factors: 3 methods of the soil tillage and 5 methods of sulphur fertilization. The first factor – the conservation ridge methods of soil tillage: A – summer (plough skimming, ridge forming, seeding of white mustard), B – autumn (plough skimming, seeding of white mustard, cultivation, ridge forming) and C – spring (plough skimming, seeding of white mustard). The second factor – rate and form of sulphur fertilization: 1 – Control (without S), 2–25 kg S per ha in form SO42-, 3–25 kg S-elemental per ha, 4–50 kg S per ha in form SO42-, 5–50 kg S-elemental per ha. The highest biological and commercial yield of tubers and the economic results (also the best economic effectiveness index and production costs of 1 ton of potato tuber) was found when ridges were prepared in autumn or summer, and 25 and 50 kg ha-1 S applied in sulfate and elemental form, respectively. Using the soil tillage with forming ridges in autumn with 50 kg S per ha (elemental and sulfate) and 25 kg S per ha applied in sulfate gave the best financial surplus.