The invention discloses a guide sleeve type hydraulic cylinder achieving sealing through an axial structure dynamic-pressure clearance. The guide sleeve type hydraulic cylinder comprises a cylinder body, a piston, a piston rod, a guide sleeve and a cylinder cover. An inward-concaved groove is formed in the surface of an inner hole of the guide sleeve in the circumferential direction of the guide sleeve in a through manner. The inward-concaved groove is of a front-and-back symmetry structure and comprises an annular oil groove and a V-shaped conic face. The annular oil groove is located in themiddle, in the front-and-back direction, of the inward-concaved groove. The V-shaped conic face is arranged in front-and-back symmetry relative to the annular oil groove and comprises a front conic face and a back conic face which are sequentially arranged from inside to outside. A V-shaped structure is jointly formed by the front conic face and the back conic face. The top ends of the front conicface and the back conic face are connected with the surface of the inner hole of the guide sleeve, and the bottom ends of the front conic face and the back conic face are connected with the top end of the groove edge of the annular oil groove. The top end of the front conic face does not communicate with the inner end of the guide sleeve, and the top end of the back conic face does not communicate with the outer end of the guide sleeve. According to the guide sleeve type hydraulic cylinder, the leakage amount can be effectively reduced on the premise of guaranteeing liquid lubricating betweenthe guide sleeve and the piston rod.