To provide a starching pretreatment method for laundry in cleaning for business purposes which facilitates starching of the laundry, prevents the alkali burn of the starched laundry in spite of finishing next day, does not give rise to environmental pollution in spite of discharging of cleaning water as it is to rivers and saves resources as just one time of rinsing is necessitated.

This starching pretreatment method for the laundry in cleaning for business purposes comprises setting the water level of a washing basket for cleaning at a middle water level, putting the cleaning water therein, putting the laundry and a proper amount of an alkaline detergent into the washing basket, subjecting the laundry to regular washing for about 15 minutes at around adequate temperature 55°C, then setting the water level of the washing basket at a high level without draining, putting the cleaning water therein, regulating the pH to 6.00 to 7.00 with a neutralizing agent, cleaning the laundry for about 5 minutes at around 45°C, performing rising once after draining and weak dehydrating, then starching the laundry, thereby making the finish of the laundry white.