The problem of calculating the number of Adam isomorphic classes of circulant is discussed in this paper. Here we obtained the formulae of enumeration of the following isomorphic classes of circu lants:i) (n

2)={C.(a1

a2

)|(a1

a2

n)=1;a1

a2≠0且a1≠a2} where n is prime power. ii) (n

2)={Cn(a1

a2)|(a1

n)=1;a1

a2且≠a1≠a2}

iii) (p

q)={C

an

a2

…

aq)|≤ai≤p-1

ai≠0 i=1

2

…q)

where p

q is prine and q