Modern trends in food habits are moving towards fast food outlets due to the busy lifestyle of people all over the world. Due to consumption of foods with excessive amount of Trans Fatty Acids (TFA), may leads to heart and other chronicle diseases. Therefore, with a view to study presence of TFA and changes occurrence on fatty acid profile during baking and cooking, thirteen bakery and fast food products were selected for this study. These products were purchased from premier food outlets in Sri Lankan market and subjected to analyze TFA and SFA by adapting respective protocols relevant to derivatization by ester formation, gas chromatography-mass spectrometry for individual separation and identification following total fat isolation by microwave-assisted soxhlet extraction. Results of the study revealed that total fat percentages of the bakery products and fast foods were ranging from 3.705 ± 0.224 to 26.732 ± 0.662 and from 7.805 ± 0.230 to 14.546 ± 0.477 respectively. Based on the fatty acid profile analysis and the availability of SFAs of all the products were ranging from 20.543 ± 0.334 to 43.109 ± 0.411and TFAs from 20.758 ± 0.239 to 39.975 ± 0.377. However, two bakery products namely fish bun and fish patty did not contain TFAs. According to this study, availability of TFA and SFA in most of processed foods were (E)-octadec-9-enoic acid (elaidic acid) and hexadecanoic acid (palmitic acid) respectively.