The invention discloses a double-station machine picked cotton processing process image information online acquisition device. The device comprises a cotton sample online obtaining part, a double-station optical glass plate and a double-station image acquisition part, the cotton sample online obtaining part is arranged in a cotton conveying pipeline used for picked cotton processing, and a cotton sample is pressed on the double-station optical glass plate to make the double-station image acquisition part at the other side of the double-station optical glass plate acquire information of the cotton sample; and the cotton sample online obtaining part comprises a servo motor, a cotton sample pressing plate and a sampling tank, the cotton sample pressing plate is arranged in the sampling tank, the output shaft of the motor is connected with one end of the cotton sample pressing plate, and the motor drives the cotton sample pressing plate to rotate along the connecting end in order to press and take the cotton sample of the cotton conveying pipeline. The device improves the acquiring efficiency of the image of the cotton sample increases understanding of information of cotton in the cotton conveying pipeline, reduces the processing and manufacturing cost of a single device, has the characteristics of rapidness, accuracy, real time and accuracy in sampling, and in favor of knowing the parameters of a machine picked cotton processing technology in real time.