Abstract: Tropical cyclone is one of the major weather disasters affecting coastal areas, which can produce high winds and heavy rains, posing serious threats to the safety of people's lives and property in coastal areas. China is in the Northwest Pacific, which is affected more frequently by tropical cyclones than any other area in the world. Therefore, it is of great significance to strengthen the research on tropical cyclone in the Northwest Pacific. In recent years, observations and studies have proved that lightning activity often occurs in tropical cyclone, which is closely related to the convective evolution and intensity variation of tropical cyclone. Based on data of lightning imaging sensor (LIS) carried on the TRMM (Tropical Rainfall Measuring Mission) satellite during 1998-2014, the characteristics of lightning properties (including duration, extended distance, channel area and optical radiant energy) of tropical cyclone in the Northwest Pacific are studied by establishing the lightning dataset of tropical cyclone in the region. The results show that all attributes of tropical cyclone lightning present lognormal distribution characteristics, and the distribution of peak values of these attributes is consistent with that of the Northwest Pacific thunderstorm system, but different from that of East Asia land thunderstorm system. The maximum of tropical cyclone lightning tends to occur over the ocean at tropical depression intensity levels. The maximum proportion of lightning in the outer rain belt is the lowest, while the maximum proportion of the duration and optical radiant energy of lightning in the inner core is the highest. The tropical cyclone lightning duration of different intensity levels has no significant difference, but the mean value of lightning spatial scale and optical radiation energy of tropical storm are lower than those of tropical depression and typhoon. For different areas of tropical cyclone, the maximum value of duration and optical radiant energy of core lightning decrease with the increase of distance between lightning and tropical cyclone center. In terms of maritime-continental contrasts, tropical cyclone lightning occurs over the ocean with larger spatial scale and stronger optical radiant energy than that over the land, while lightning duration is roughly the same. After tropical cyclone landing, the spatial scale of lightning decreases and the optical radiant energy of lightning weakens. Compared with non-tropical cyclone lightning, tropical cyclone lightning has shorter extension distance, narrower channel area and weaker optical radiant energy, but the average duration of lightning is longer.