Abstract: In the critical stage of fighting COVID-19, the partner assistance relationship of "each province supporting a city" provided effective assistance to the epidemic areas in Hubei province (other prefecture-level cities except Wuhan city, the same below). Advanced medical teams and resources as well as the emergency management experience of public crisis were brought from aid-providing areas to the aid-receiving areas. This paper researches the information disclosure of receiving and distributing anti-epidemic provisions by the charity organizations, and tests the spatial spillover effect of partner assistance on charitable organizations' information disclosure. It is found that during the period of partner assistance, the more timely and in more details anti-epidemic provisions are disclosed in the aid-providing areas, the more so it is in the aid-receiving areas, and vice versa. The supervision effect of media report and the demonstration effect of contact learning can both enhance the spatial spillover effect. The main findings are still significant after alternative measurement, correction of measurement error, elimination of historical inertia, consideration of Internet partner assistance and consideration of time series correlation. The empirical conclusion can help further understand the law of information disclosure of anti-epidemic funds and substances and promote the cross-regional collaborative governance mechanism of charitable organizations.

Key words: partner assistance, spatial spillover effect, charitable organizations, provisions against epidemic diseases, information disclosure