A binding device comprising: a plurality of binding rod portions (12,20,30,20A,30A), connecting regions for connecting the plurality of binding rod portions, and pivot coupling regions serving as the center for opening/closing of binding rods (12,20,30,20A,30A) composing the binding rod portions; wherein the binding rods composing the binding rod portions are provided to project at an appropriate interval therebetween in a longitudinal direction of the connecting regions and/or pivot coupling regions of a first binding device member and a second binding device member from the connecting regions and/or pivot coupling regions of the first binding device member and the second binding device member so that binding rods of the first binding device member and the second binding device member face each other; moreover the first binding rod of the first binding device member and the second binding rod of the second binding device member are configured to turn the first binding rod and/or the second binding rod in the opposite direction to the expanding direction of the first binding rod and the second binding rod; the first binding device member and/or the second binding device member have a pressing portion(s) (140,142,144) provided to project from a connecting region and/or a pivot coupling region in the extending direction of the center for opening/closing the binding rods; the pressing portion (s) are configured to displace the first binding device member and/or the second binding device member to the extending direction of the center for opening/closing the binding rods, characterised in that the binding rod portions have binding rod latching portions (22,32) for latching when the binding rods are closed, the binding rod latching portion being formed at free ends (20b,30b) of the binding rods in a side opposite to base portions (20a,30a) provided continuously to the connecting region and/or the pivot coupling region; the binding rod latching portions are formed so as to relatively move the binding rods, which are to be latched in a direction intersecting with a turning direction of the binding rods to be latched, so that the binding rod latching portions latch or disengage the binding rods; the first binding rod of the first binding device member and the second binding rod of the second binding device member disengage the first binding rod latching portion and the second binding rod latching portion by relatively moving in the longitudinal direction of the connecting region in the pivot coupling region, and in that an elastic member has the binding rod latching portion of the first binding rod and the binding rod latching portion of the second binding rod to engage with each other when the binding rod portion are closed; and in that the pressing portion(s) are provided to project from the end of a connecting region of the first binding device member and/or the second binding device member and/or the end of a pivot coupling region toward a side opposite to the direction of disengagement in the side opposite to the direction of relatively moving the binding rods and disengaging the binding rods so as to be pressed directly or indirectly with finger in order to disengage the plurality of the first binding rods of the first binding device member from the plurality of the binding rod latching portions of the second binding rods of the second binding device member in the opposing other side, and and in that the first binding rod of the first binding device member and/or the second binding rod of the second binding device member relatively move and disengage the disengagement between the binding rod latching portion of the first binding rod and the binding rod latching portion of the second binding rod against the spring force of the elastic member by pressing the pressing portions directly or indirectly with fingers, moreover the pressing portions are configured to turn the first binding rod and/or the second binding rod in the opposite direction to the expanding direction of the first binding rod and the second binding rod.