"Chi's Sweet Home" centers on a young kitten named Chi, who becomes separated from her mother and siblings after wandering away from her home. Lost and alone, Chi is discovered by a young boy named Yohei Yamada and his family, who decide to take her in despite living in a pet-free apartment complex. The series chronicles Chi's adjustment to her new life with the Yamada family, capturing her playful curiosity, mischievous antics, and gradual bonding with her human caretakers.

The narrative unfolds through episodic vignettes, each highlighting Chi's daily adventures and interactions. From learning to use the litter box to exploring the apartment and encountering household objects for the first time, Chi's experiences are portrayed with a blend of humor and warmth. The Yamada family, including Yohei, his parents, and occasionally his grandmother, navigate the challenges of secretly raising a kitten while fostering a loving environment for her. Their efforts to hide Chi from their landlord and neighbors add a layer of tension and comedy to the story.

Chi's interactions extend beyond the Yamada household. She befriends other animals in the neighborhood, such as a large black cat named Blackie and a fluffy white cat named Cocchi. These relationships provide insight into Chi's growing understanding of the world and her place within it. The series also explores themes of family, responsibility, and the bond between humans and animals, all while maintaining a lighthearted and accessible tone.

The animation style is simple yet expressive, emphasizing Chi's wide-eyed innocence and the everyday charm of her surroundings. The series balances moments of gentle humor with heartfelt emotion, making it appealing to both children and adults. Through its episodic structure, "Chi's Sweet Home" offers a heartwarming portrayal of a kitten's journey from vulnerability to belonging, underscored by the enduring affection of her adoptive family.