The invention discloses a stability margin estimation method and a control method for a pull type bicycle. A method for dynamically estimating stability margins is designed. The coordinates of a ZMP and three grounding points in a geodetic coordinate system are calculated through attitude detection data; a parallel line of each edge is made through the ZMP; three maximum trapezoids are formed by the parallel lines in a grounding triangle and the corresponding edges; the stability margins of the edges in a dynamic state can be obtained by calculating the ratios of the areas of the three maximumtrapezoids to the area of the current grounded triangle; and the stability margins of the edges in the dynamic state are used as a data basis for balance control. The method for dynamically estimating the stability margins can estimate the stability margins of the edges of the grounding triangle in dynamic operation in real time; and the balance of the pull type bicycle is controlled in a real-time, dynamic and quantified mode by taking the stability margins of the edges of the dynamic grounding triangle as the data basis, so that the estimation and control are more targeted and more accurate.