Lactococcus lactis has been associated with cheese manufacturing. It is important that the cultures used are able to survive to adverse heat conditions in manufacturing of probiotic process cheese. The hypothesis was whether prior exposure to mild heat would enhance heat tolerance of L. lactis. The objective was to evaluate the effect of prior exposure to mild heat on the growth of Lactococcus lactis. L. lactis R-604 was subjected to heat shock at 40 or 50°C for 1 h. Control was not subjected to heat shock. Cultures were subsequently incubated for 24 h at 30°C followed by subjecting them to batch pasteurization (for ice cream mix) at 71.11°C for 30 min. M17 Agar with 10% w/v lactose was used for plating. Plates were incubated aerobically at 30°C for 48 h. Each experiment was conducted 3 times. Counts observed after subjecting mildly heat treated L. lactis to batch pasteurization were 4.4 Log for 40°C, 4.3 Log at 50°C, and 1 Log for the control. Exposure of L. lactis R-604 to mild heat enhanced its tolerance to heat (batch pasteurization).