| In this article we calculate the breaking masses of octet baryons from QCD. QCD is the fundamental theory of strong interaction. It is a much important problem that calculate the masses of hadronic particles from the chiral perturbation theory of QCD. We can calculate the masses of hadrons in hadron levels or in quark levels. In hadron levels the hadronic masses can be introduced phenomenologically. We met much difficulties when consider the calculations in quark levels, we need to define the wave functions of hadron states, so we must think about the three bodies problem, we cann't overcome it. Because we cann't catch the structure of hadrons exactly, also we can evaluate it by construct models, this is not our way. In low energy we can take hadrons as particles of a dot have no size and shape. In high energy we must consider the thorough and exact structure of hadrons.Consider the matrix elements 3qλ3q + c8qλ8q|B>, where the baryon states | B > is define in hadron levels. We want to add the informations of quark levels in the hadrons which we take them as particles of a dot have no size and shape. We represent the quark current operators with path integral in QCD framework. Firstly, we construct QCD lagrangian with external fields. We get the quark current operators which act on baryon states through the derivative of functional defined by QCD lagrangian with respect of external fields. Think about spontaneous breaking, the QCD lagrangian is invariant when the quark masses is vanish. For baryon states | B>, we will construct hadronic effective lagrangian in hadron levels. We construct unit effective lagrangian which include external fields and satisfy chiral symmetry bytransformation character of external fields, the part informations of quark fields has been included in. Thus external fields link quark fields and hadron fields together. Expand the functional define by the hadronic effective lagrangian with external fields in perturbative way to one loop. We obtain the evaluation of matrix elements on which quark currents act through the derivative with respect of the external fields and set the external fields zero. This idea was first advanced by Weinberg and Gasser'4' etc. We extend to SU(3) from SU(2).
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