Abstract: Predecessors did not consider the dissolved shale gas in kerogen when calculating the shale gas reserves. But it has been proved by some researchers that large amount of shale gas dissolved in kerogen can not be ignored in the calculation. The reserves calculation method ignoring the dissolved gas in kerogen can’t be used to truly and accurately calculate the reserves in shale gas reservoirs. Based on the previous calculation methods for shale gas reserves, a new material balance equation is established considering adsorbed phase density, volumetric variations of matrix and fracture pores with pressure, changes of adsorbed phase volume with pressure and dissolved gas in kerogen. Case study shows that dissolved gas accounts for about 4.69% of the total reserves. Reserves of free gas, adsorbed gas and total gas will be overestimated if dissolved gas is not taken into consideration. Therefore, in order to ensure the accuracy of reserves calculation, dissolved gas must be taken into account in the reserves calculation