An automobile door latch device includes: a mesh mechanism; a body; a base; and an operation mechanism disposed on the base, the operation mechanism including: an outside lever configured to receive an operating force of an outside handle to perform open actuation; a first open lever configured to perform open actuation in conjunction with open actuation of the outside lever; a locking/unlocking mechanism; a second open lever configured to perform open actuation in conjunction with open actuation of the first open lever output from the locking/unlocking mechanism; and a fully open release lever configured to perform open actuation in conjunction with open actuation of the first open lever, wherein the fully open release lever is connected to an operating force transmission member configured to transmit the open actuation of the fully open release lever to a fully opening latch device for holding the slide door in a fully open position.