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We present the optical (V, R, and I) photometry for BL Lacertae, which wasobserved from 1997 through 1999, with the 1.56-m telescope at the Shanghaiastronomical observatory (SHAO). After the 1997 outburst, it dimmed to a lowstate and then brightened again. During the period JD 2450701 to JD 2450701.5,variations of 0.40mag, 0.27mag, and 0.21mag over a time scale of 100 minuteswere found for V, R, and I bands, suggesting that the variations weredecreasing with wavelength.  The correlation between V, R, and I is also analyzed using the  DCF (Discrete Correlation Function) method. This shows that the variabilityin the V, R, and I bands are correlated with no time delay longer than 0.2 day.Comment: 16 pages, 3 figures, 1 table, accepted to A&

Optical observations of BL Lacertae from 1997 to 1999