We present deep UBV(RI)C charge-coupled device (CCD) photometry for the young open star clusters Tr 1 and Be 11. The CCD data for Be 11 are obtained for the first time. The sample consists of ~1500 stars reaching down to V~21mag. Analysis of the radial distribution of the stellar surface density indicates that radius values for Tr 1 and Be 11 are 2.3 and 1.5pc, respectively. The interstellar extinction across the face of the imaged clusters region seems to be non-uniform with a mean value of E(B-V)=0.60+/-0.05 and 0.95+/-0.05mag for Tr 1 and Be 11, respectively. A random positional variation of E(B-V) is present in both the clusters. In the cluster Be 11, the reason for the random positional variation may be the apparent association of the H II region (S 213). The 2MASS JHK data in combination with the optical data in the cluster Be 11 yield E(J-K)=0.40+/-0.20mag and E(V-K)=2.20+/-0.20mag. Colour excess diagrams indicate a normal interstellar extinction law in the direction of the cluster Be 11.