Noting increasing consumption of energy and fossil fuel sources and their poluting effects, it is necessary to find renewable and clean sources of energy which can substitute fossil fuels. To meet this demand industrial societies elect use of biomass and converting it into biogas and bioethanol as sustainable and clear energies . The first and most important step in biomass conversion to bioenergy is pretreating them to change their structure and chemical construction in order to increase and fluence the yield of hydrocarbon particles hydrolysis into monomeric sugars. Nowadays, in some industrial societies some plants like wheat are cultivated only for bioenergy prodution.These plants are an important source of starch and lignocellulose. Moreover it can be found huge mixtures of starchy and lignicellulosic in agriculture and municiple solid wastes. In order not to destruct starchy components in harsh conditions applied for lignocellulosic components hydrolysis, they should be separated which need high cost and long times. There are rare researches about the possibility of accessibility to a conditions in which dilute-acid hydrolysis pretreatment results in maximum production and minimum destruction of fermantable monomeric sugars and conversion to inhibitors. This project can divided into three stages. In the first stage dilute-acid hydrolysis of pure cellulose (Avicel) and starch was done at the range of middle temperatures 70-150°C, time 0-40 minutes, acid concentration 0-1% (v/v) and material concentration 5-15(w/v). In this stage the software and Central Composite Design was used for experimental design and analysis. In the optimized condition of 130°C, 30 minute, acid concentration of 1% and material concentration of 7.5% almost all of the starch was converted into glucose whitout inhibitor production. However maximum yield of glucose production from cellulose was in the optimized condition of 150°C, 40 minute, acid concentration of 1% and material concentration of 15% in which only 3.3% of cellulose converted into glucose. But in this operation condition the amount of glucose in starch hydrolyzate intensively decreased because of destruction. Therefore with due attention to very low conversion of cellulose, the mentioned conditions for total conversion of starch to glucose was chosen as optimized condtion of dilute-acid hydrolysis pretreatment and in the second stage pine wood and potatoe as representatives of lignocellulosic and
