The phage phiKZ is a jumbo bacteriophage that infects Pseudomonas aeruginosa. As in other myoviruses, its 200 nm-long tail is composed of an inner rigid tube and a contractile sheath. Upon adsorption to the bacterium, the tail sheath is contracted, pushing the tube against the bacterial wall. This movement makes a hole in the wall, which is used to eject the phage genome into the bacterium. Here, we present the structure of the tail sheath and tail tube a 3.5 Å resolution. They reveal a 6-fold and helical structure similar to other contractile-tailed phages. Each tail sheath protein has extensions that make contacts with 6 other copies, creating a mesh. The void space above and below each protein leave space for the contraction. In the tail tube, the arrangement of the protein in this rigid tube is more compact than in the tail sheath. Besides, each copy has long extensions that intertwined with the neighbouring copies. The structure of both the tail sheath and the tail tube protein is well conserved due to its importance in the phage cycle.