A lamp with a temperature-controlled automatically protecting circuit which includes a temperature induction circuit and a sampling circuit with its input end to connect with an output end of the temperature induction circuit, wherein the temperature control automatically protecting circuit further includes: a comparing circuit which has an input end to connect with an output end of the sampling circuit and when a positive voltage drop across the sampling resistance of the sampling circuit is lower than a reference voltage, the comparing circuit will have a high electrical level output; a trigger circuit which has an input end to connect with an output end of the comparing circuit and a thyristor which can be triggered by the high electrical level output of the comparing circuit to have the trigger circuit in the on state; and a maintaining circuit which has a capacitance in parallel with the thyristor in the trigger circuit and which, after being in series with a resistance, have a low electric level output to the protected operational circuit.