Objective To compare the dosimetric difference between anisotropic analytical algorithm(AAA)and pencil beam convolution(PBC)for intensity modulated radiation therapy(IMRT)Plans in esophageal carcioma.Methods For nine esophageal cancer cases,IMRT plan(five fixed-fields),which calculated with AAA and PBC,were generated by Varian Eclipse 8.6 treatment planning systerm.The COMPASS dose verification system was used to verify these plans.The difference of dose distribution to target and organs at risk(OAR)was compared.Results The gamma pass rates of GTV,PTV,lung and heart in AAA were higher than PBC(P<0.05).There were significant differences in Dmean、V100%、HI of GTV,and there were only significant differences in HI of PTV.AAA had more advantages.The two algorithm in double lung index between the difference was significant differences.But,the difference of AAA was smaller.The differences of heart`s Dmean,V30,V40 in two algorithm were similar(P>0.05).The D01 of spinal cord in planned value is higher than the measured value,the difference was 1.56±0.25%for AAA and 4.48±1.13%for PBC.Conclusion Esophageal carcioma radiotherapy using the AAA algorithm is more accurate than using the PBC algorithm.