We obtained multi-colour light curves of HH Boo .
We analysed the orbital period variation of the system .
The analysis indicated that there is possible mass transfer from the second component to the primary or mass loss with -5.04 \times 10 ^ { -7 } M _ { \odot } per year .
Re-analysing the available radial velocity curve , we analysed the light curves .
The inclination ( i ) of the system was found to be 69 ^ { \circ } .71 \pm 0 ^ { \circ } .16 , while the semi-major axis ( a ) was computed as 2.246 \pm 0.064 R _ { \odot } .
The mass of the primary component was found to be 0.92 \pm 0.08 M _ { \odot } , while it was obtained as 0.58 \pm 0.06 M _ { \odot } for the secondary component .
The radius of the primary component was computed as 0.98 \pm 0.03 R _ { \odot } , while it was computed as 0.80 \pm 0.02 R _ { \odot } for the secondary component .
We demonstrated that HH Boo should be a member of the A-type subclass of W UMa binaries .