The invention discloses a continuous soil nutrient detecting device which comprises a moving mechanism, a sampling mechanism, a detecting mechanism and a sealing and storing mechanism; the moving mechanism comprises a moving shell; a supporting frame is connected with the top surface of the moving shell; the sampling mechanism and the detecting mechanism each comprise a sampling shell and a detecting shell; the sampling shell is arranged at the bottom of the moving shell and is connected with the detecting shell through a soil transporting pipeline; the detecting shell is fixed on the supporting frame; a sealing and storing pipeline is connected with the bottom end of the detecting shell; a sealing and storing valve is mounted at the joint of the sealing and storing pipeline and the detecting shell; the sealing and storing mechanism comprises a sealing and storing conveying belt mounted on the top surface of the moving shell; the sealing and storing conveying belt is positioned under the sealing and storing pipeline. The continuous soil nutrient detecting device disclosed by the invention has the benefits that deep soil can be detected, so that detection results are more precise; to-be-detected soil can be taken out for sealing and storage to be convenient for secondary detection and verification; sampling and detection can be simultaneously performed, so that the detection efficiency is higher; therefore, the continuous soil nutrient detecting device is worthy of popularization.