A modular frame structure for a wall in glass or other pane material, comprising: a lower side or base extending along a predefined first longitudinal extension, with a base pane seat suitable to receive and lock an edge portion of a pane, an upper side or cross member extending along a predefined second longitudinal extension, with a cross member pane seat suitable to receive and lock an edge portion of a pane, one or more posts, extending along a longitudinal axis, suitable to form at least one side of the frame, with at least one post pane seat suitable to receive and lock a portion of a pane, connecting means, suitable to ensure a connection between said posts and said lower and upper sides, said posts comprise a reinforcing bar suitable to confer stiffness to said frame structure, said connecting means comprise a first undercut coupling seat obtained on said lower side, a second undercut coupling seat obtained on said upper side, said first and second undercut coupling seats (27, 28) extending, respectively, along said longitudinal extension (100, 100') of said lower and upper sides and first and second coupling portions (29, 30) of said post, said first coupling portion being insertable in said first undercut coupling seat in any points of said longitudinal extension, said second coupling portion being insertable in said second undercut coupling seat in any points of said longitudinal extension, said first and second coupling portions (29, 30) being selectively couplable between a release position, in which said first and second coupling portions (29, 30) do not engage said first and second undercut coupling seats (27, 28), respectively, and an engaging position, in which said first and second coupling portions (29, 30) engage said first and second undercut coupling seats (27, 28), respectively; characterized in that: said coupling portions (29, 30) are obtained as end portions of the reinforcing bar; said coupling portions (29, 30) comprise a neck which is extended along the longitudinal axis of the post, connected in a single piece with a central portion of the reinforcing bar in one hand, and with an end portion on the other hand, such end portion bearing at least one projection overhanging in a direction substantially transverse to the neck, which, in the engaging configuration, is extended into at least one undercut (33, 58) of the first and second undercut coupling seat (27, 28); said coupling portions (29, 30) are coupled with clearance to the first and second undercut coupling seat (27, 28). a lower side or base extending along a predefined first longitudinal extension, with a base pane seat suitable to receive and lock an edge portion of a pane, an upper side or cross member extending along a predefined second longitudinal extension, with a cross member pane seat suitable to receive and lock an edge portion of a pane, one or more posts, extending along a longitudinal axis, suitable to form at least one side of the frame, with at least one post pane seat suitable to receive and lock a portion of a pane, connecting means, suitable to ensure a connection between said posts and said lower and upper sides, said posts comprise a reinforcing bar suitable to confer stiffness to said frame structure, said connecting means comprise a first undercut coupling seat obtained on said lower side, a second undercut coupling seat obtained on said upper side, said first and second undercut coupling seats (27, 28) extending, respectively, along said longitudinal extension (100, 100') of said lower and upper sides and first and second coupling portions (29, 30) of said post, said first coupling portion being insertable in said first undercut coupling seat in any points of said longitudinal extension, said second coupling portion being insertable in said second undercut coupling seat in any points of said longitudinal extension, said first and second coupling portions (29, 30) being selectively couplable between a release position, in which said first and second coupling portions (29, 30) do not engage said first and second undercut coupling seats (27, 28), respectively, and an engaging position, in which said first and second coupling portions (29, 30) engage said first and second undercut coupling seats (27, 28), respectively; characterized in that: said coupling portions (29, 30) are obtained as end portions of the reinforcing bar; said coupling portions (29, 30) comprise a neck which is extended along the longitudinal axis of the post, connected in a single piece with a central portion of the reinforcing bar in one hand, and with an end portion on the other hand, such end portion bearing at least one projection overhanging in a direction substantially transverse to the neck, which, in the engaging configuration, is extended into at least one undercut (33, 58) of the first and second undercut coupling seat (27, 28); said coupling portions (29, 30) are coupled with clearance to the first and second undercut coupling seat (27, 28). said coupling portions (29, 30) are obtained as end portions of the reinforcing bar; said coupling portions (29, 30) comprise a neck which is extended along the longitudinal axis of the post, connected in a single piece with a central portion of the reinforcing bar in one hand, and with an end portion on the other hand, such end portion bearing at least one projection overhanging in a direction substantially transverse to the neck, which, in the engaging configuration, is extended into at least one undercut (33, 58) of the first and second undercut coupling seat (27, 28); said coupling portions (29, 30) are coupled with clearance to the first and second undercut coupling seat (27, 28).