Provided is an in-line processing system for agricultural products, configured to automatically and uniformly process agricultural products such as vegetables and fruits, thereby achieving work convenience and allowing quick workability as well as efficiently commercializing various agricultural products after harvesting. The in-line processing system for agricultural products comprises: a washing processor having a washing chamber for receiving, the inside thereof, agricultural products to be processed and configured to wash the agricultural products through spray and immersion operations performed in the washing chamber； a cutting processor configured to feed and slice the washed agricultural products； a steaming processor configured to accommodate the sliced agricultural products in a colander while unfolding the agricultural products and generate overheated steam therein to treat the agricultural products with heat for a predetermined time； a dry processor having a dry chamber maintained at a temperature of 40-50°；C and provided to receive the agricultural products therein, and configured to supply hot air to the dry chamber while humidifying and ventilating the same to dry the agricultural products； a selection processor having a first selector configured to firstly select the agricultural products according to a size through vibration while moving the agricultural products supplied from the dry processer, and a second selector configured to secondarily select the agricultural products that have passed through the first selector by detecting the colors of the agricultural products； and a raw material transfer unit having an upper portion, on which the agricultural products are placed, disposed in overall work processing intervals from the washing processor to the selection processor, and configured to transfer and supply the agricultural products. The raw material transfer unit includes a bypass transfer unit which has a transfer path connected from the wash
