Abstract: With the speeding up of urbanization, more and more high buildings emerge, which makes the vertical spatial growth of city become the most obvious landscape in the past decades. The research on urban vertical growth becomes a necessity. But the previous researches have just considered the urban area extends while neglected the vertical spatial growth, so they can not explain the actual urban structure comprehensively. This paper aims to analyze this variable and dynamic phenomenon during the process of urbanization by the application of modification to urban allometric growth model and C-D function, which is used widely in the research of urban geography. The method urban allmetric growth analysis can be further modified to ensure that they can explain the urban growth comprehensively both in horizontal and vertical dimension. In this paper, we introduce a new variable representing for urban vertical growth and take Dalian City as an empirical evidence implication. Set up the nonlinear allometric growth functions:A(t)＝aP(t)^b,H(t)＝aP(t)^b, Y＝P^αA^β h^γ,combine the urban area sprawling with urban vertical spatial growth together, analyzing the nonlinear allometric growth interactions among these urban spatial factors and urban population size. We think this work will contribute to understand the concept of fractal urban space and the structure of urban dynamic system more clearly. Taking Dalian city as a case study, we find some conclusions: (1) by the means of urban allometric growth analysis, the urban land-use of Dalian City witnesses the transformation from the pattern of "urban area sprawling (1904-1985)" to "urban vertical spatial growth as well as the area sprawling (1985-1992)" to "urban vertical spatial growth (1992-2000)". (2) By the means of urban input-output structure analysis and the Cobb-Douglas function, we can see after 1992, the value of "Y-P" input-output coefficients ξ is on the decline, while the value of "Y-A", "Y-h" input-output coefficients ξ both grow increasingly, this tendency reflects the overall growth of urban land-use including both horizontal and vertical spatial growth. (3) With regards to urban land-use, the pattern of optimizing irrational production, distribution structure and the environmental improvement would have much more input-output economic benefit than just extending the urban area. So in the process of urbanization, we should pay more attention to optimizing irrational land-use distribution and structure instead of enlarging urban area blindly.