A dual lumen microcatheter , comprising a first catheter body having a proximal-end segment (S1), a transition segment (S2), and a distal-end segment (S3) that are connected in sequence, and a second catheter body engaged to a periphery of the first catheter body , the second catheter body has a connecting segment (K1) engaged to the periphery of the first catheter body and a tapered tip segment (K2) connected to the connecting segment (K1); the first catheter body has a first guide wire inner lumen slidably receiving a guide wire, and in the first catheter body , the proximal-end segment (S1) has a first inner layer forming the first guide wire inner lumen, a spring layer wound on the first inner layer in winding manner and arranged along a length of the first inner layer , a woven layer provided on an outer side of the spring layer , and a first type polymer layer covering an outer side of the woven layer ; the transition segment (S2) has the first inner layer extending from the proximal-end segment (S1), a woven layer extending from the proximal-end segment (S1) and partially covering an outer side of the first inner layer , and the first type polymer layer extending from the proximal-end segment (S1) and covering the outer side of the woven layer ; the distal-end segment (S3) has the first inner layer extending from the transition segment (S2) and the first type polymer layer extending from the transition segment (S2) and covering the outer side of the first inner layer ; the second catheter body has a second guide wire inner lumen slidably receiving a guide wire; the second catheter body has a second inner layer forming the second guide wire inner lumen and a second type polymer layer covering an outer side of the second inner layer ; the connecting segment (K1) of the second catheter body is at least partially connected to the transition segment (S2) of the first catheter body . a first catheter body having a proximal-end segment (S1), a transition segment (S2), and a distal-end segment (S3) that are connected in sequence, and a second catheter body engaged to a periphery of the first catheter body , the second catheter body has a connecting segment (K1) engaged to the periphery of the first catheter body and a tapered tip segment (K2) connected to the connecting segment (K1); the first catheter body has a first guide wire inner lumen slidably receiving a guide wire, and in the first catheter body , the proximal-end segment (S1) has a first inner layer forming the first guide wire inner lumen, a spring layer wound on the first inner layer in winding manner and arranged along a length of the first inner layer , a woven layer provided on an outer side of the spring layer , and a first type polymer layer covering an outer side of the woven layer ; the transition segment (S2) has the first inner layer extending from the proximal-end segment (S1), a woven layer extending from the proximal-end segment (S1) and partially covering an outer side of the first inner layer , and the first type polymer layer extending from the proximal-end segment (S1) and covering the outer side of the woven layer ; the distal-end segment (S3) has the first inner layer extending from the transition segment (S2) and the first type polymer layer extending from the transition segment (S2) and covering the outer side of the first inner layer ; the second catheter body has a second guide wire inner lumen slidably receiving a guide wire; the second catheter body has a second inner layer forming the second guide wire inner lumen and a second type polymer layer covering an outer side of the second inner layer ; the connecting segment (K1) of the second catheter body is at least partially connected to the transition segment (S2) of the first catheter body . <EOS>