Woody biomass used as alternative fuel to generate power becomes a significant element of sustainability nowadays. Biomass is usually stored for some period before direct combustion or processing in biorefineries. The objective of this study is to quantify and compare the gas emissions from Western Red Cedar (WRC) and Douglas fir (DF) chips during storage at a range of temperatures (5-50oC) under both non-aerobic and aerobic conditions. Results showed that the dominant mechanism is different depending on the stored materials. Emissions of CO and CH4 were 2-5 orders of magnitude less than CO2 emission for both WRC and DF chips. The major components of VOCs detected by GC/MS from both materials are similar, consisting of hydrocarbons, aldehyde, terpenes, methanol, acetone, ketone, acid and esters, benzene and its derivatives. The total concentrations of VOC (TVOC) under both conditions differed with temperature, and they were much higher from the DF chips than WRC. The emission factors under the aerobic condition were higher when compared to those under the non-aerobic condition over the storage time period.