The design of the MB.155 started in late 1939 by the engineer Fandeux. the purpose of the design was to find a way to create a new plane based on the Mb.152 with improved range and maneuverability. the most evident feature of the MB.155 was the dump of the engine hood was now nearly invisible. the new engine Gnome-Rhône 14N-49 of 1.180 was installed and the cockpit was a little moved to the back to allow a larger fuel tank. the armament was sigly upgraded with the addition of two 7.5mm MAC 34 mg along side of the two HS 404 20mm cannon and the other two 7.5mm of the MB.152. the plane was still at the state of prototype when it was put into service out of nessessity. the french air-force used 10 MB.155 in their army durring the battle of france. the test of the plane wasn't officially finished but the performance and reliability was sastifactory for the service. after the french surrender, the german autorized the production of 20 additional Mb.155 for vichy. 19 of those plane was stationed near the city of Montpelier. after the liberation, the German seized the Mb.155 and put them into the Luffwaffe to serve into  training schools.The Luftwaffe used  in total about forty Bloch 155, mainly in the JG 103 and Jagdlehruberprufungsgruppe  in Orleans-Bricy then Orange-Caritat.
Type Single seat fighter
Engine 1 Gnome-Rhône 14N-49 with a 3-bladed variable pitch propeller, Chauviere
Dimensions Length 9,104 m, , height 3,96 m ,  span 10,542 m , wing area 17,32 m2  ,
Weights Empty 2140 kg, loaded 2850 kg , max. take off weight 2900 kg , wing loading 155,4 kg/m2, fuel 720 l
Performance Max.. speed 520 km/h , cruising speed 460 km/h , range 750 km , endurance  , service ceiling  11740 m , climb 7 min. to 4000 m
Armament 2 20 mm Hispano-Suiza HS 404 with 60 rpg, 2 7,5 mm MAC 1934 M39 machine guns with 500 rpg or 4 7,5 mm MAC 1934 M39 with 500 rpg