A mobile terminal provided with a security function, the mobile terminal comprising: a casing comprising a data input portion for inputting data and an upper casing and a lower casing which are capable of assembled or disassembled with respect to each other; a circuit board comprising a security unit that is electrically connected to the data input portion and requiring security, and processing input data; an anti-tampering conduction portion arranged between the casing and the circuit board and electrically connected to the circuit board by being pressed when the upper casing and the lower casing are assembled to each other; and a control portion denying access to data of the security unit based on a resistance value of the anti-tampering conduction portion, characterized by further comprising: a security partition configured to encompass the security unit to deny access to the data of the security unit from a side portion of the casing, wherein the circuit board comprises a lower circuit board arranged above the lower casing and an upper circuit board arranged above the lower circuit board, the security partition is arranged between the upper circuit board and the lower circuit board and comprises a lower security partition connected to the lower circuit board and an upper security partition arranged above the lower security partition and connected to the upper circuit board, and the anti-tampering conduction portion is arranged between the upper circuit board and the lower circuit board and comprises a plurality of anti-tampering prevention members separated from one another, each of the plurality of anti-tampering prevention members being electrically connected to at least two of the upper circuit board, the lower circuit board, the upper security partition, and the lower security partition. a casing comprising a data input portion for inputting data and an upper casing and a lower casing which are capable of assembled or disassembled with respect to each other; a circuit board comprising a security unit that is electrically connected to the data input portion and requiring security, and processing input data; an anti-tampering conduction portion arranged between the casing and the circuit board and electrically connected to the circuit board by being pressed when the upper casing and the lower casing are assembled to each other; and a control portion denying access to data of the security unit based on a resistance value of the anti-tampering conduction portion, characterized by further comprising: a security partition configured to encompass the security unit to deny access to the data of the security unit from a side portion of the casing, wherein the circuit board comprises a lower circuit board arranged above the lower casing and an upper circuit board arranged above the lower circuit board, the security partition is arranged between the upper circuit board and the lower circuit board and comprises a lower security partition connected to the lower circuit board and an upper security partition arranged above the lower security partition and connected to the upper circuit board, and the anti-tampering conduction portion is arranged between the upper circuit board and the lower circuit board and comprises a plurality of anti-tampering prevention members separated from one another, each of the plurality of anti-tampering prevention members being electrically connected to at least two of the upper circuit board, the lower circuit board, the upper security partition, and the lower security partition. a security partition configured to encompass the security unit to deny access to the data of the security unit from a side portion of the casing, wherein the circuit board comprises a lower circuit board arranged above the lower casing and an upper circuit board arranged above the lower circuit board, the security partition is arranged between the upper circuit board and the lower circuit board and comprises a lower security partition connected to the lower circuit board and an upper security partition arranged above the lower security partition and connected to the upper circuit board, and the anti-tampering conduction portion is arranged between the upper circuit board and the lower circuit board and comprises a plurality of anti-tampering prevention members separated from one another, each of the plurality of anti-tampering prevention members being electrically connected to at least two of the upper circuit board, the lower circuit board, the upper security partition, and the lower security partition.