[目的/意义]随着网络平台的多元化，用户越来越倾向于横跨多个平台开展信息交流活动，因此，聚焦跨平台用户，探究其互动类型，识别其中的高价值互动并分析其形成路径，对理解用户的跨平台信息交流行为具有重要意义。[方法/过程]通过对齐在代表性社会化分享平台和短视频平台上进行跨平台互动的博主，获取其2023年全年发布内容下的所有评论，基于K-means方法实现互动类型划分，识别高价值互动类型，并分析其形成路径。[结果/结论]跨平台博主与受众之间的双向互动可以分为活跃互动和松散互动两类，两类互动都更多的出现在社会化分享平台，活跃互动相较于松散互动互动频率更高、涉及主题更广、二者关系更亲密，有助于互动双方形成社会资本，可视为人际关系的线上扩展形式，是一种高价值互动。而此种高价值互动形成需要经过单向注意、表面接触和相互卷入3个阶段，主要有赞许贡献型、需求交流型、关心分享型3种形成路径，其中，赞许贡献型是社会化分享平台出现最多的类型，需求交流型是短视频平台出现最多的类型，关心分享型则在两类平台中均较少出现。

[Purpose/significance] With the diversification of online platforms, users are increasingly inclined to carry out information exchange activities across multiple platforms, therefore, focusing on cross-platform users, exploring their interaction types, identifying high-value interactions and analyzing the path of their formation are of great signifi⁃cance in understanding cross-platform users' information exchange behaviors. [Method/process] By aligning bloggers who have cross-platform interactions on representative social sharing platforms and short-video platforms, and obtain⁃ing all comments under the content they posted throughout the year of 2023, we implement the division of interaction types based on the K-means method to identify high-value interactions and analyze their formation paths. [Result/con⁃clusion] Two-way interactions between cross-platform bloggers and audiences can be divided into two categories: ac⁃tive interactions and loose interactions, both of which appear more often on the social sharing platforms. Active interac⁃tions are more frequent, involve a wider range of topics, and have a more intimate relationship than loose interactions,
which helps both parties to form social capital, and can be regarded as an online extension of interpersonal relation⁃ships, and is a high-value interaction. The formation of such high-value interaction needs to go through three stages:one-way attention, surface contact and mutual involvement, and there are three main formation paths: approval-contri⁃bution type, demand-exchange type and care-sharing type, among which approval-contribution type is the type that appears most frequently on social sharing platforms, demand-exchange type is the type that occurs the most on shortvideo platforms, and care-sharing type is the type that occurs less often on both platforms.