In order to solve the technical problem of extracting rice row curvature information in paddy field environment, a tactile sensing method was proposed. According to the mechanical difference and the physiological height of rice and weeds during the weeding period, a kind of tactile beam which was based on bending sensor was designed. Though the mechanical analysis, a dynamic model of the contact between tactile beam and rice seedlings was established. Combined with the bending strength of rice seedling, the principle of the bending rigidity of the tactile beam was determined. Through building the tactile beam calibration test bench, the functional relationship between the device offset and the pressure difference of tactile beam was obtained. On this basis, based on multisensor technology, according to the voltage characteristics generated by the four tactile beams, the calculation method of rice seedling bending was proposed. In order to verify the measurement accuracy and the stability of the device, several field experiments were carried out. The test of speed of travel showed that the acceleration of travel speed was harmful to the stability. At the speed of 1.5m/s, the average relative error was 5.90mm and the maximum error was 830mm. The test of rice hole number indicated that the measurement error became lowest when the number of rice hole was more than 6 and the average error was 2.56mm. The average error was 6.17mm when the number of rice hole was between 1 and 3. The average error was 4.36mm when the number of rice hole was between 4 and 5. The test of water layer thickness indicated that there was no significant correlation between measurement errors and water layer thickness and the lateral offset of neighboring rice seedlings can be controlled within 14mm. The measurement result of this device can satisfy the requirement of accurate control such as rice mechanical weeding avoiding plants and provide new ideas and examples to solve the problem of crop identification and detection in the paddy field environment. 