The objectives of the present research is to appreciate the effect of synthesizing parameters on engineering properties of Geopolymer composites manufactured using locally available low calcium fly ash . Fly ash used are lignite coal based and falls under class F category. The current research utilizes low calcium fly ash obtained from a thermal power plant located near Kolkata, India. The broad areas of present research include: Manufacturing of Geopolymer and a comprehensive study on the effect of synthesizing parameters on compressive strength of Geopolymer paste. The effect of synthesizing parameters such as Alkali content (Na2O/Al2O3), Silica content (SiO2/Al2O3) and Water to Geopolymer binder ratio have been studied and arrived at certain level of understanding regarding manufacturing and compressive strength, which will be useful to the researchers and manufacturers.