The thermal needle probe method, commonly used to measure the thermal conductivity λ of soils, uses a long, thin metallic probe with a temperature sensor and a line heater inside. However, it is very challenging to insert these probes into consolidated or highly compacted soils or rocks; this often results in probe buckling and significant disruption of the surrounding ground, which compromises the accuracy of the data. To get around these issues and yet provide accurate thermal conductivity readings, we discovered from a previous article that it was possible to mount a thermal needle probe using a pre-drilled hole filled with thermally conductive grease. However, as the size of the sensor can affect the device's sensitivity performance, a microneedle-based sensor to boost accuracy and produce accurate data to improve performance was suggested. This chapter presents a fully integrated microneedle-based sensor and gives a thorough analysis of its composition, individual parts, and uses. This can aid in the referral of highly accurate data for future research, enabling soil quality management to recommend appropriate decisions for future events.