Two-dimensional (2D) multiferroic materials have garnered broad interests attributed to their fascinating magnetoelectric properties and energy-efficient multifunctional device applications. Multiferroic heterostructures have recently been realized, nevertheless, the direct coupling between ferroelectric and ferromagnetic order in a single material still remains a daunting challenge, especially for 2D materials. Herein, we develope a simple physical vapor deposition approach to synthesize 2D p-doped SnSe. The local phase segregation of SnSe2 microdomains and accompanying interfacial charge transfer result in the emergence of degenerate semiconductor and metallic feature in SnSe. Intriguingly, the room-temperature ferrimagnetism has been demonstrated first in 2D p-doped SnSe with the Curie temperature approaching to ~337 K. Meanwhile, the robust in-plane ferroelectricity is maintained even under the depolarizing field introduced by SnSe2. The coexistence of ferrimagnetism and ferroelectricity in 2D metallic p-doped SnSe verifies its multiferroic feature. This work presents a significant advance for exploring the magnetoelectric coupling in 2D limit and constructing high-performance logic devices to extend Moore's law.