Increasing demands and concerns for reliable supply of liquid transportation fuels make it important to find alternatives to petroleum-based fuels. One such alternative is ethanol made from cellulosic biomass. Considerable investigations have been conducted to evaluate the viability of cellulosic ethanol production in several aspects (including cost competitiveness). Cost estimates of cellulosic ethanol production have been reported by many researchers in order to evaluate the economic viability of cellulosic ethanol production. However, the reported cost estimates in the literature have a large variation. The current literature contains limited reviews on the cost estimates of cellulosic ethanol production and mostly focused on some individual processes. This paper presents a literature review on the cost estimates of entire cellulosic ethanol production. It reviews the estimated costs for both the entire cycle (from planting to conversion) and individual processes for cellulosic ethanol production. It also covers factors that lead to variations among reported cost estimates.