Aim: Direct kidney involvement in B‐cell lymphoproliferative disease is a rare disorder with only a few studies reported in Caucasian patients. The clinicopathological characteristics and outcome of this entity remain poorly described. Methods: We retrospectively studied all adult Chinese patients who had histology‐proven renal parenchymal infiltration by malignant B‐cells between 1 January 2000 and 31 December 2018 at two tertiary hospitals in Hong Kong. Clinical, pathological and radiological data were collected from 20 patients. Follow‐up data were analysed until 31 December 2019. Results: Median follow‐up duration was 22 (1–171) months. Only seven patients (35%) had established diagnosis of haematological cancer before kidney biopsy. Diffuse large B‐cell lymphoma (DLBCL) was the most common subtype in our cohort (n = 5, 25%). Others included low‐grade B‐cell lymphoma (n = 11), intravascular large B‐cell lymphoma (n = 1), mantle cell lymphoma (n = 1) and multiple myeloma (n = 2). Fourteen patients (70%) presented with AKI while 12 patients (60%) had proteinuria. Seven patients (35%) had unilateral renal mass, one had bilateral renal masses and one had bilateral diffuse nephromegaly in computed tomography. Lymphomatous tubulointerstitial infiltration was the prevalent histological finding. Nine patients (45%) had coexisting renal lesions other than direct tumour infiltration. All but one patient received chemotherapy. Ten patients died and renal responders had a significantly better survival than non‐renal responders (p =.03). Conclusion: Direct tumour infiltration can occur in a wide variety of B‐cell lymphoproliferative disorders. Coexisting immunoglobulin‐related nephropathy is frequently found. Renal biopsy is required for early diagnosis which allows timely and appropriate treatment. SUMMARY AT A GLANCE: The authors report a series of 20 Chinese patients presenting with B‐cell lymphoproliferative diseases directly infiltrating the kidney, which is an uncommon but important condition that requires early tissue diagnosis and specific therapy. The need to be aware of this problem, as hinted by characteristic clinical and pathological features, is highlighted. [ABSTRACT FROM AUTHOR]