To better understand the substituent effect of cyclic catalysts on propylene polymerization, a series of cyclic bis(phenoxyimine) titanium catalysts bearing different size substituents at the ortho position of the phenolate ring and fluorine atoms of varied positions on the N-aryl moiety were synthesized, and their propylene polymerization performances were investigated upon activation with methylaluminoxane (MAO). The experimental results suggested that polymerization behaviors such as activity, polymer molecular weight, and dispersity as well as stereoregularity were largely adjusted by steric and electronic effects of ligand substituents. The polymerization activity was mainly influenced by the substituents on the N-aryl moiety. The catalysts with ortho-F on the N-aryl moiety exhibited the lowest activity among the series of catalysts with the same substituent ortho to phenolate ring. Differently, introducing meta-F to the aryl of imine moiety greatly enhanced the polymerization activity (15-30 times higher than that of the analogous catalyst with ortho-F) coupled with faster chain transfer, which generated lower-molecular weight polypropylene with narrower distribution. The beneficial electronic effect provided by meta-F also played a significant role in controlling isotacticity of polypropylene in our system, which was rarely reported. DFT computation revealed that the polymerization regioselectivity could be altered by the steric effect of the substituents ortho to the phenolate ring and the electronic effect of fluorine on the N-aryl moiety. In addition, different positions of fluorine atoms on the N-aryl moiety resulted in a notable difference in regioselectivity and stereoselectivity by changing the insertion energy barrier of the corresponding transition states. Moreover, we successfully explored the functionalization reactions of the highly stereoregular isotactic polypropylene using low-molecular weight polymers obtained.