Taking into account the global climate change problem, an urgent task is greenhouse gas (GHG) emissions reduction, and associated with this problem the uncertainty analysis of input data and results of GHG inventory. The main purpose of this investigation is the assessment of inventory uncertainty at the level of separate company, region and even country in the industrial sector (including emission processes caused by chemical and physical transformation of materials, as well as by burning of fuels). We discuss the obtained results of spatial GHG inventory in the Industry sector in Poland, by usage of the bottom-up approach, based on IPCC guidelines, official statistics and digital maps of territories investigated. Monte-Carlo method was applied for estimation of inventory uncertainty in main categories of analyzed sector, taking into account the small and large variation of parameters in cases of symmetric and asymmetric distributions. We determined emission sources that have the greatest impact on overall uncertainty in the industrial sector, and evaluated the relative uncertainty depending on uncertainty in activity data and emission factors. The additional knowledge on spatial distribution of emissions and their structure, supports the processes of decisions making on emission reduction.