Orientational order parameters (OOP) in the smectic C and nematic phases of heptyloxyazoxybenzene (HAB) have been determined from x-ray diffraction and refractive index studies. Order parameters determined from x-ray studies have been corrected for the random orientation of the director in a cone in the smectic C phase of HAB. The causes of discrepancy between the experimental and theoretical OOP values have been discussed.