A plastic bag with a closure tape, including: a bag formed by one or more flexible plastic films attached to one another defining bag walls, a closed bottom, an upper opening which allows accessing the inside of said bag , and an annular fold attached to the bag walls defining a conduit or several consecutive segments of conduit around the mentioned upper opening , the inside of said conduit or of each of said segments of conduit being accessible through at least one aperture provided in said fold ; at least one closure tape formed by a flexible plastic film arranged inside the conduit with the ends thereof attached forming a ring around the opening , or inside at least one of the segments of conduit with the ends thereof attached to opposite ends of said segment of conduit ; a portion of said closure tape being accessible through said at least one aperture for partially extracting it from inside the conduit or from inside the segment of conduit , causing the closure of the opening ; wherein said closure tape is folded in the center along a folding line parallel to the longest edge of the closure tape ; characterized in that said closure tape is printed on one of its faces with first messages arranged in a reading direction (D1); said first messages are entirely located in one of the two halves of the closure tape demarcated by the folding line , second messages , identical to the first messages , are printed entirely in the other one of the two halves of the closure tape demarcated by the folding line , arranged in a reversed reading direction (D2) with respect to the reading direction (D1); and the walls of the bag and/or of the fold are transparent or translucent, which allows viewing the first messages and/or the second messages of the closure tape through same. a bag formed by one or more flexible plastic films attached to one another defining bag walls, a closed bottom, an upper opening which allows accessing the inside of said bag , and an annular fold attached to the bag walls defining a conduit or several consecutive segments of conduit around the mentioned upper opening , the inside of said conduit or of each of said segments of conduit being accessible through at least one aperture provided in said fold ; at least one closure tape formed by a flexible plastic film arranged inside the conduit with the ends thereof attached forming a ring around the opening , or inside at least one of the segments of conduit with the ends thereof attached to opposite ends of said segment of conduit ; a portion of said closure tape being accessible through said at least one aperture for partially extracting it from inside the conduit or from inside the segment of conduit , causing the closure of the opening ; wherein said closure tape is folded in the center along a folding line parallel to the longest edge of the closure tape ; characterized in that said closure tape is printed on one of its faces with first messages arranged in a reading direction (D1); said first messages are entirely located in one of the two halves of the closure tape demarcated by the folding line , second messages , identical to the first messages , are printed entirely in the other one of the two halves of the closure tape demarcated by the folding line , arranged in a reversed reading direction (D2) with respect to the reading direction (D1); and the walls of the bag and/or of the fold are transparent or translucent, which allows viewing the first messages and/or the second messages of the closure tape through same. <EOS>