The present disclosure discloses a camera lens and a calibration method of field-depth for the camera lens. The camera lens includes a lens module, a central processing unit and a thermal expansion compensation module. The lens module includes a first lens and a second lens with a baseline length b2 to the first lens. The first lens includes a first lens unit formed on same glass substrate and a second lens unit with a baseline length b1 to the first lens unit. The baseline length change value between the second lens and the first lens can be calculated. Therefore the thermal expansion of the camera lens can be calibrated.