An ankle orthosis, comprising: a longitudinal shaft which extends from the heel over the ankle and is open at the side of the tibia; a sole element connected to the shaft and at least partially covering the sole of the foot, a first strap for fixing the shaft to the lower leg and a second strap for fixing the sole element to the foot, characterized in that: a) said shaft and said sole element each comprise an inflexible section (1 a, 2a) and a flexible section (1b, 2b), said inflexible shaft section extending from a plantar position below the heel laterally upwards over and above one ankle and having one part of a first hook and loop fastener in the area of its proximal edge and said flexible shaft section (1 b) extending contralaterally from the heel upwards over and above the other ankle, said inflexible sole section extending from the heel to the arch of the foot and said flexible sole section extending at least from the arch of the foot towards the toes; b) said first strap is fixed to the distal edge of the flexible shaft section (1 b), has the second part of the first hook and loop fastener at its end and is sufficiently long so that the two parts (3a, 3b) of the first hook and loop fastener can be joined to one another; c) said second strap is fixed to the distal end of the inflexible sole section and comprises two parts (4a, 4b) of a second hook and loop fastener, one part of said second hook and loop fastener being provided at the end of said second strap and the other part being provided in a middle part and on the opposite side of said second strap, said second strap being sufficiently long so that the two parts (4a, 4b) of the second hook and loop fastener can be joined to one another when the second strap is laid across the dorsum of the foot and around both ankles; and d) a third strap is fastened to the distal end of said inflexible sole section, said third strap comprising two parts (5a, 5b) of a third hook and loop fastener, one part of said third hook and loop fastener being provided at the end of said third strap and the other part being provided in a middle part and on the opposite side of said third strap, said third strap being sufficiently long so that the two parts (5a, 5b) of said third hook and loop fastener can be joined to one another when the third strap is laid around the foot. a) said shaft and said sole element each comprise an inflexible section (1 a, 2a) and a flexible section (1b, 2b), said inflexible shaft section extending from a plantar position below the heel laterally upwards over and above one ankle and having one part of a first hook and loop fastener in the area of its proximal edge and said flexible shaft section (1 b) extending contralaterally from the heel upwards over and above the other ankle, said inflexible sole section extending from the heel to the arch of the foot and said flexible sole section extending at least from the arch of the foot towards the toes; b) said first strap is fixed to the distal edge of the flexible shaft section (1 b), has the second part of the first hook and loop fastener at its end and is sufficiently long so that the two parts (3a, 3b) of the first hook and loop fastener can be joined to one another; c) said second strap is fixed to the distal end of the inflexible sole section and comprises two parts (4a, 4b) of a second hook and loop fastener, one part of said second hook and loop fastener being provided at the end of said second strap and the other part being provided in a middle part and on the opposite side of said second strap, said second strap being sufficiently long so that the two parts (4a, 4b) of the second hook and loop fastener can be joined to one another when the second strap is laid across the dorsum of the foot and around both ankles; and d) a third strap is fastened to the distal end of said inflexible sole section, said third strap comprising two parts (5a, 5b) of a third hook and loop fastener,