Tobacco farming as an agricultural development issue, has been identified among others as an important theme to study the relationship of its production to deforestation. This study was carried out in Tutuo ward, Sikonge district in Tabora region to assess land use changes due to switch from tobacco to sunflower as an alternative cash crop; and its influence on deforestation. The villages namely Usanganya, Mole and Tutuo were involved. Household questionnaire, checklists, participant observation, PRA techniques and remote sensing were employed for data collection. Logistic regression models, linear regression analysis and geographic information system techniques were used to analyse factors influencing farmers switch from tobacco to sunflower, study the relationship between hactrage of sunflower replacing tobacco and the rate of deforestation and/ or regeneration of forest and analyse multi temporal Landsat TM and ETM+ satellite images respectively. Factors likely to significantly influence farmers switch from tobacco to sunflower cultivation in Tutuo ward included unreliable tobacco market and farm size; while farming experience significantly reduced the likelihood of shifting from tobacco to sunflower cultivation. The switch found to have no significant on reduction of deforestation and not favoured miombo woodland regeneration. The conclusion of this study is that land use changes due to switch from tobacco to sunflower, shows a trend of reducing deforestation and favouring regeneration of miombo woodlands. The study recommends farmers to introduce sunflower as an alternative to tobacco. The effect of the switch to poverty alleviation in terms of income from tobacco when compared to alternative crops which is less lucrative, is to be studied to have a base for the decision to before the switch. Farmers also have to reduce the volume of fuelwood consumption by establishing household woodlots, community based forest management system and construct efficient barns the efforts that contributes to reduction of deforestation.