Four new comb-shape maleic anhydride copolymeric diesters with aliphatic and/or aromatic pendant chains were synthesized by suspension polymerization and characterized by Fourier transform infrared spectroscopy (FTIR) and gel-permeation chromatography. These polymers were evaluated as pour-point depressant (PPD) and rheology modifiers on Kosamba (KS) crude oil (Gujarat, India). A complete rheological analysis of crude oil With and without additives has been carried out using an advanced rheometer AR 500. A correlation between pour-point depressing power and structure of the polymer has been established. The role of asphaltene content in the crude oil has been highlighted in connection with performance of PPD. The proposed correlation has been supported by optical microscopy.