A hood lock apparatus configured to hold a hood of a vehicle in a closed state by locking a striker (S) provided on the hood, the hood lock apparatus comprising: a base plate fixed to a vehicle body structural member of an engine compartment, the engine compartment being opened and closed by the hood, the base plate comprising a striker groove into which the striker (S) enters in response to a closing operation of the hood; a latch rotatably supported on the base plate , the latch being configured to lock the striker (S) entered into the striker groove so as not to exit from the striker groove ; a locking plate rotatably supported on the base plate , the locking plate being configured to lock the latch , which locks the striker (S), so as not to rotate; a rattle lever rotatably supported on the base plate , the rattle lever being configured to hold the striker (S), which is locked by the latch , with the latch ; and a rattle spring provided to extend between the base plate and the rattle lever , the rattle spring being configured to bias the rattle lever holding the striker (S) with the latch towards the striker (S), wherein the rattle spring is disposed to straddle a first center line (C1), the first center line (C1) passing through a rotational shaft of the rattle lever and extending in a direction which is at right angles to a direction in which the striker groove extends, wherein the latch comprises an engaging portion , wherein the rattle lever comprises an engaging portion , wherein the engaging portion of the latch and the engaging portion of the rattle lever being brought into engagement with each other so as to transmit a biasing force of the rattle spring from the rattle lever to the latch , and wherein in a state where the rattle lever holds the striker (S) with the latch being locked by the locking plate , the engaging portion of the latch and the engaging portion of the rattle lever are spaced apart from each other. a base plate fixed to a vehicle body structural member of an engine compartment, the engine compartment being opened and closed by the hood, the base plate comprising a striker groove into which the striker (S) enters in response to a closing operation of the hood; a latch rotatably supported on the base plate , the latch being configured to lock the striker (S) entered into the striker groove so as not to exit from the striker groove ; a locking plate rotatably supported on the base plate , the locking plate being configured to lock the latch , which locks the striker (S), so as not to rotate; a rattle lever rotatably supported on the base plate , the rattle lever being configured to hold the striker (S), which is locked by the latch , with the latch ; and a rattle spring provided to extend between the base plate and the rattle lever , the rattle spring being configured to bias the rattle lever holding the striker (S) with the latch towards the striker (S), wherein the rattle spring is disposed to straddle a first center line (C1), the first center line (C1) passing through a rotational shaft of the rattle lever and extending in a direction which is at right angles to a direction in which the striker groove extends, wherein the latch comprises an engaging portion , wherein the rattle lever comprises an engaging portion , wherein the engaging portion of the latch and the engaging portion of the rattle lever being brought into engagement with each other so as to transmit a biasing force of the rattle spring from the rattle lever to the latch , and wherein in a state where the rattle lever holds the striker (S) with the latch being locked by the locking plate , the engaging portion of the latch and the engaging portion of the rattle lever are spaced apart from each other. <EOS>