There is an obvious degradation tendency of alpine meadows in Northwestern Yunnan Province (NYP)because of climate change and disturbance of tourism activities. In order to identify the changes of aboveground morphological traits and biomass of plants in the process of meadow degradation in NYP, this study specified three degradation levels, i.e., degradation level 1 (R1), degradation level 2 (R2) and control check (CK), according to the width of tourism-caused paths. A field survey was conducted to obtain the data of height, lateral spread, leaf length, leaf width, blade aspect ratio and aboveground biomass of Gramineae, Cyperaceae and Forbs in late July 2018. A vegetation living state index (VLS) was constructed based on aboveground morphological traits indexes to describe a synthetic state of plants. The results showed that: 1) the height, lateral spread, leaf length and blade aspect ratio of Gramineae decreased along the degradation gradient. The height, leaf length and blade aspect ratio of Cyperaceae decreased along the degradation gradient. All of the five aboveground morphological traits of Forbs decreased along the degradation gradient. 2) Aboveground biomass of Gramineae, Cyperaceae and Forbs decreased along the degradation gradient. 3) The VLS of Gramineae, Cyperaceae and Forbs decreased along the degradation gradient. The VLS order of different functional groups in CK was Forbs > Cyperaceae > Gramineae. The VLS of Cyperaceae was higher than the VLS of Gramineae and Forbs in both R1 and R2. 4) The linear regression relationship between the VLS and aboveground biomass weakened along with degradation gradients. This study suggests that the variation of aboveground morphological traits among different functional groups may augment the uncertainty of the prediction of aboveground biomass in degraded alpine meadows in NYP.