Temperature-responsive polymers with a lower critical solution temperature (LCST) have attracted much attention in biomedical and biotechnological fields. It is important to tune their cloud point temperature (T-c) in a broad temperature range as desired by the applications. In this study, new thermo-responsive 2-hydroxy3-isopropoxypropyl starches (HIPS) was synthesized using Hylon V starch as raw material and isopropyl glycidyl ether as hydrophobic reagent. The phase transition behavior of HIPS and their T-c were determined by spectrophotometry. The effects of several conditions on the T-c of the HIPS were also investigated, which indicated that varying the molar substitution (MS) of HIPS can adjust T-c in a broad temperature range from 69 to 28 degrees C by changing the hydrophobic-hydrophilic balance of starch. The phase transition became fast and the T-c decreased with increasing polymer concentration. The effect of a series of sodium salts on the T-c of aqueous HIPS solutions was reported and the effectiveness of ions follows a trend, known as Hofmeister series. Several organic solvents were selected and the organic additives with small molecular weight can also regulate the T-c of HIPS in a certain range by changing the polymer-water interactions.