This study analyses herbicide usage in wheat - grown under dry and irrigated conditions - from economic point of view. Amasya province of Turkey was chosen as research area because wheat is a major crop grown in the study area. A survey was applied to 78 farms which 70 of them use herbicides and 8 of them do not use herbicides in wheat growing. Herbicide usage resulted in 29.09 % yield increase (from 3322.20 kg/ha to 4288.60 kg/ha) under irrigated conditions and 10.53 % under dry conditions (from 2666.70 kg/ha to 2947.50 kg/ha). Under irrigated conditions the share of total herbicide cost in variable cost and production cost were 5.77 % and 3.69 %, respectively. Under dry conditions the values were found as 5.28 %, and 3.81 %, respectively. Gross profit was higher in the farms using herbicides (181.47 $/ha) than those not using herbicides (28.06 $/ha) under irrigated conditions. But, under dry conditions it was low in the fon-ner (45.38 $/ha), compared to the latter (74.38 $/ha). Gain threshold under both irrigated and dry conditions were calculated as 244.40 kg/ha, and 176.40 kg/ha wheat, respectively.