∵圆C1:x2+y2+2x+8y-8=0的圆心C1(-1,-4),半径r1= 1 2 4+64+32 =5,圆C2:x2+y2-4x-4y-1=0的圆心C2(2,2),半径r2= 1 2 16+16+4 =3,∴|C1C2|= ((2+1)2+(2+4)2 =3 5 ,|r1-r2|=2,r1+r2=8 ,∵|r1-r2|<|C1C2|<r1+r2,∴圆C1与圆C2相交.故选C.